The question of a workers' government arises in Greece only because it has been raised in a certain form by Syriza, and only because they have come to hegemonise the left workers' vote.  Current (unofficial) polling seems to indicate they have up to 35% of the vote, though there is still a great deal of volatility, and some recent polls have even given New Democracy a very narrow lead.  Nonetheless, with anything close 35% of the vote, they would be in a position to lead a government of the left.  So, a great deal rests on why Syriza are in the position they're in.  

Explanations for Syriza's success built on the insight that reformism is a first port of call for workers in struggle aren't wrong, but they are rather complacent and general.  Apart from anything else, Syriza aren't classical reformists.  Syriza comprises a coalition between  a Eurocommunist bloc, Synaspismos, which has roots in a breakaway from the Communist Party (KKE) in 1968, and various Maoist and Trotskyist groups.  The Eurocommunists are by far the dominant force, having comprised about 85% of the members before a rightist split in 2010, which I'll come back to.  But of course, they have their own internal differentiations, as Eurocommunism has always had its left and right currents, historically oscillating between centrism and reformism.  The Maoist group, the Communist Organization of Greece (KOE), is the second largest organisation in the coalition.  Alongside them are the Trotskyist group, the International Workers Left, and the Communist Left for Ecology and Renewal.  The trajectory and composition of these hetroclite elements are discussed by Stathis Kouvelakis here (original here).  Essentially, we are talking about divisions, redivisions, and realignments within the communist and non-communist left, with the leading role taken by a Eurocommunist organisation with an orientation toward what used to be called the 'new social movements'.  Not a typical reformism, then, and certainly more akin at an ideological level to Die Linke than to traditional social democracy.  Moreover, they're far from the only reformist option for workers, a point we will return to.

A refinement of the same argument is that since Greeks are overwhelmingly opposed to the Memorandum, yet simultaneously opposed to withdrawal from the euro, it is logical that Syriza, which favours continued membership of the Eurozone on a reformed basis, should have benefited from PASOK's collapse.  Hence, workers are gravitating to a reformist solution that matches their 'level of consciousness'.  

Again, though more specific, this explanation is inadequate to the complexity of reality.  Polls show that about half of Greeks oppose remaining in the euro if it means sticking with the measures contained in the Memorandum, and these voters are overwhelmingly concentrated in the base of the left parties, including more than two thirds of Syriza voters.  In other words, their attitude to the EU is context-driven.  Syriza itself is not that simple either.  As Kouvelakis has pointed out: 1) its position is that the EU can be internally reformed "but on the basis of denouncing all the existing European Treaties (Maastricht, Lisbon etc)"; 2) it contains other currents hostile to the EU, including significant Trotskyist and Maoist groups who comprise about 15% of the membership; 3) most importantly, its position on austerity is inconsistent with its pro-European stance, an ambiguity whose resolution will depend significantly on the continuation and outcome of struggles in which Syriza is partially embedded.

Recall, moreover, that it looked for a while as if a right-wing breakaway from Syriza, the Democratic Left (DIMAR) would be the main beneficiary.  DIMAR represented the 'Europeanist' Ananeotiki wing of Synaspismos, the dominant Eurocommunist component of Syriza.  It departed amid some grievance over the leftist direction in which the leadership of Alexis Tsipras was taking the coalition, and took with it the former leader of Syriza, four sitting MPs, and hundreds of members.  It selected Fotis Kouvelis as its leader, and lauded its attitude of "responsibility and accountability" before the press.  Strictly in terms of its programme and its attitude to austerity, it was somewhere between Syriza and PASOK, and slightly to the right of the Greens with whom it shared enough to cooperate in the 2010 regional elections.  After the May elections, Kouvelis even indicated that he would be willing to join a coalition government with some of the austerity parties if Syriza could be persuaded to join.  So, having thus launched itself as both a critic of austerity and a 'responsible party of government', at one stage it had 15% in the polls.  That is not far short of what Syriza actually received in the recent parliamentary elections.  There was no necessary reason, if what mattered was a pro-European anti-austerity stance, why Syriza should have overtaken them.  Syriza haven't just won people on their main programmatic points; they've won the trust of millions of workers and, at that, the most radicalised workers.

It is also true, but inadequate, to say that Syriza is the beneficiary of militant struggles including 17 general strikes, several mass demonstrations, workplace occupations, and the spread of rank and file organisation.  Syriza has benefited from this, but it has not been as important to these struggles as the KKE, so it was not inevitable that it should do so.  Likewise, that Syriza's claim on the majority of the left workers' vote is only a recent development, following from the formation of a PASOK-led coalition government, is true, but doesn't itself explain why Syriza should have benefited.  

There are, of course, many determining factors, but I would suggest that a key determination was Syriza raising the slogan of a left government to stop austerity.  This immediately distinguished it from its two main left electoral rivals - the respectability-hugging DIMAR, and the sectier-than-thou KKE.  This is why Syriza could win the election with about a third of the vote, much of which it coming at the expense of other left parties.  The Communists (KKE) have lost the most, with their vote pushed down to about 5%.  The anticapitalist left coalition ANTARSYA have also been squeezed, from 1.2% to about 0.5%.  DIMAR appears to be relatively steady on 7.5%. 

Of course, the KKE remains a powerful force in the workers' movement, but it is suffering from its appallingly sectarian position.  Not only does it refuse to work with Syriza, but in true Third Period fashion it actually denounces them far more than it does the Nazis or the parties of the Memorandum.  Its combination of militancy and sectarianism is partially rooted in the antiquated and mortified analysis of 'monopoly capitalism', and partially in its view of its role as the vanguard party uniquely tasked with taking on the EU and the 'monopolists'.  At any rate, the KKE have decided to make the EU the main point of division when it is clear that for most left-wing Greek workers, that is not the main antagonism.

Possibly, the KKE will comfort themselves with the idea that their electoral perdition is temporary, that soon the ideological and political vapours giving rise to Syrizismo will dispel as the KKE edge out their left rivals and take the leadership of the workers' movement.  But their strong industrial position is not written in stone, and this isn't just another election.  The choice is between a New Democracy-led austerity government, which would be immensely demoralising, and a Syriza-led anti-austerity government, which would give the whole continental left a massive shot in the arm and open up a host of new possibilities.  This is a key moment in which a great deal is condensed, which will be formative of a great deal of the political and ideological terrain for some time, and any formation that appears to bring the latter possibility closer isn't helping the industrial struggle.  The best hope is that the KKE's delegates will be persuaded to give a vote of confidence in a Syriza-led minority government, and support its measures from the opposition benches, even if they refuse to join it.  But one still can't be sure that they aren't waiting for the chance to say, "first the Golden Dawn, then us".

As for ANTARSYA, they are standing without illusions, expecting to incur a humiliatingly low vote.  They intend to use the electoral platform to organise around and push for a programme of anticapitalist transition.  You may say that it is unlikely that this programme will benefit from an electoral drubbing.  You may add that since the main locus of their leadership is in the industrial and social struggles, since that is where they are a most serious force, this is probably where such a programme could be raised most effectively.  And, going further, you might assert that in this election, with the stakes this high, the presence of ANTARSYA candidates is unlikely to add any new dynamic to the electoral contest, thus actually increasing the turnout among left voters.  You may say that say none of the usual reasons for the far left running no-hope election campaigns apply, while unusual ones why they shouldn't, do.  You may say all that.  I couldn't possibly comment, except to nod vigorously and say 'well, yes, of course'.

Nonetheless, the majority of Greece's left-wing workers will support Syriza in their attempt to form a left government.  And that may be enough to give them a parliamentary majority, or at least a working minority government, which can then revoke the laws implementing the Memorandum.  No small thing, this, if it happens.

Now, judging from online conversations and opinion pieces, a large section of the far left is waiting for the other shoe to drop.  The narratives of betrayal are already being readied, the old verities being 'proved' repeatedly.  There are many variations, but the core of it is that: 1) Syriza are straightforwardly reformists, notwithstanding the substantial revolutionary fringe - the tail does not wag the dog; 2) reformists are apt to compromise with the forces of capitalism, and as such a sell-out of the working class cannot be long following Syriza's election.  In its latest instantiation, this is expressed in the tutting, sighing, and fanning of armpits over Tsipras chatting up the G20.  There it is: the betrayal is already afoot, the reformists already making deals with the bosses.  Perhaps so, but thus far Syriza have not withdrawn from their fundamental commitments, which are: abrogate the Memorandum, and stop austerity measures.  They did not do so when there was pressure to do so after the last election, and are not doing so now.  

I would advise caution on this line of critique, therefore: it is very well to criticise what Syriza has actually said and done, but it isn't necessary to second guess what Syriza will do.  The point will be to support the mass movements capable of pressuring a Syriza-led government from the left.  No, they are not a revolutionary formation; no, they won't overthrow capitalism; no, their manifesto is not a communist manifesto.  Yet it is just possible that Syriza won't betray workers in the interests of European capital, and that all the stern augury will have been displacement activity.

Of course there is an unresolved tension at the heart of Syriza's agenda.  Of course they can't break the austerity deadlock within the EU.  But it is not inevitable that they will resolve it by capitulation.  For what it's worth, I think they know very well that the their policy will not be tolerable to the EU's masters.  I think the talk of Europe's leaders not being willing to see Greece exit is a knowing bluff.  Of course, the Merkozy consensus is weaker than before, and may well be weakened still by Spain's ongoing crisis, or by another plunge in Italy.  But one can't envision at any stage the EU's leadership allowing themselves to give in to a junior, peripheral EU state.  Tsipras talks about Greece joining Europe as an equal and a partner - that is exactly what the EU's leadership will never allow.  So, I think the Syriza strategy is simply to avoid being blamed for Greece being forced out, in view of the potentially apocalyptic consequences of doing so.  This is perfectly understandable, even if it is a position that one could not admit from a marxist perspective, since it means basically fudging the problem that the quasi-colonial, class-structured hierarchies of the EU can possibly be reformed, but they cannot be reformed away.  The latter is a problem that will return, even if a Syriza success is followed by a graceful default, and a 'Grexit' under the most benign circumstances, and it has to be faced.

Moreover, the strongest likelihood for a Syriza-led government is that it will be in perpetual crisis.  It would be a spot-lit enclave, under constant assault from capital and the media.  One could well imagine that the severity of the social crisis, and the pressure from European capital, would force splits in such a government and bring about its early downfall.  On the other hand, there would also be a pressure, which should be resisted, on the rank and file to temper its criticisms, and curtail its actions, in order to help 'our' government as it came under capitalist attack.  The best way to 'save' such a government from capital would be to keep up the pressure and organisation, but not everyone would see it this way.  And even if Syriza would lack a sufficient basis in the leadership of the workers' movement to effect a quietening of class struggle, it would have undoubted authority within the movement.  So, these divisions would not merely be in the party of government, but would exert effects throughout the resistance.  The election of a Syriza-led government will be a nodal point, not the end point, in the process of workers finding a solution to the problem.  

However, I suggest you should compare those antagonisms to the sorts of demoralising splits and recriminations that would likely follow from a New Democracy victory and the prolonged imposition of austerity.  Relatively speaking, the crisis of a Syriza government would be a benevolent crisis.  This is Syriza's challenge: the good crisis, or the bad crisis?  The first radical left government in Europe for a generation, in a situation more serious than any radical movement has faced since the Carnation Revolution, the further exacerbation of divisions in the European bourgeoisie, a step forward for the Greek and all European workers' movements, and possibly a new and uncertain terrain?  Or, terra firma, in permanent opposition and division, with our weaknesses and hesitancy constantly making up for those of the bourgeoisie?