Whatever party wins today's election in Greece, the austerity and reform measures agreed with the EU last year as the price for €240bn in loans are already dead. Politicians and bankers in the rest of Europe have reacted with near hysteria to the swift rise and possible electoral success of the radical leftist party Syriza. They take at face value its pledge to tear up the austerity memorandum with the EU, so widely detested here, as soon as it takes office. They are not-so-quietly rooting for the conservative New Democracy and its previous coalition partner, Pasok, parties formally committed to austerity and to staying in Europe.

In practice, the Syriza leader, Alexis Tsipras, is saying openly only what New Democracy members hint at privately. The majority of Greeks want to stay in the eurozone, but reject the programme of tax rises combined with salary, pension, job and public expenditure cuts, which they see as leading them inevitably and permanently to a Third World standard of living. The economics professor Efkilidis Tsakalotos, from the University of Athens and a Syriza leader, told me that his party wants the euro, but refuses to allow Greece "to be reduced to a sub-Saharan standard of living".

Even Greeks agreeing with EU prescriptions for reforming the corrupt and dysfunctional Greek state say this is no longer feasible. George Tzogopoulos, a fellow of the Bodossakis Foundation think tank, last year believed that Greece was passing up an opportunity for reform by not taking advantage of the troika (EU, IMF and European Central Bank) proposals. But today he says: "It is too late to implement reform, because society is exhausted." Reform has become unenforceable because it is associated with the crippling austerity package.

There is a further absurdity in the EU approach to the Greek crisis. This is to expect the leaders of New Democracy and Pasok, the parties that have misruled Greece for the past 30 years, to take charge of cleaning up the mess from which they have done so well. No wonder ordinary Greeks feel they are being swindled once again and see the EU memorandum as a German diktat proposing neo-liberal formulae that will impoverish them further.

Mr Tzogopoulos says the troika had been ill-informed about how power is exercised in Greece. Berlin and Brussels knew and cared little about the country, though regarding it with distrust, until the economic crisis exploded in 2009. Greek leaders were almost equally ignorant, the government not even knowing how many people it employed (734,000) until July 2010.

In the last days of campaigning, New Democracy has played up the theme that only it and its coalition partners are pro-European and a vote for Syriza is a vote for exit from the euro and for economic calamity. There are signs this approach is proving successful at frightening voters. At the party's final rally in Syntagma Square on Friday night, the crowd waved blue-and-white Greek flags to the sound of apocalyptic music and speakers chanted "we vote to remain in the euro". Those viewing the rally on television would have received a misleading impression of the size and enthusiasm of the event, in which what two Greek observers privately called "a pathetically small crowd" was orchestrated by party managers to give an impression of vast numbers expressing unbridled enthusiasm for Antonis Samaras, the New Democracy leader. (The BBC commentary I saw of the rally played along with this orchestration, with the camera never panning over the empty spaces in the square.)

Many of the New Democracy flag-wavers were old, often retired, civil servants. They repeated the mantra that a vote for Syriza was a vote for Communism, euro exit and economic disaster. But many mentioned that they expected Mr Samaras to negotiate with Brussels to soften the austerity measures. Pota Tsopela, a retired civil servant from Pylos, said: "We think the Europeans will accept changes and allow us to bring down taxes now that [François] Hollande is in power in France." Mary Skouarta, a housewife, said: "These are crucial elections because we vote for Europe. When other countries are struggling to enter the EU, should we leave? After the election we will be able to change the [austerity] measures." She recalled that Mr Samaras had stood out against them for 17 months and had signed last year only under duress.

The previous night, I had been to a slightly larger, but still not impressive, final rally by Syriza in Omonia Square. Demonstrators were much younger, reflecting the first-round poll on 6 May when the party came first among those under 50. Antigone Sacher, a schoolteacher who had seen her salary cut, said: "I am not scared by what TV and the media are telling us about disaster if Syriza wins. We need a change." Valinos Dyonisius, a chemistry teacher, added: "We want out of austerity, not out of Europe." He thought that New Democracy would come first in the poll, and thereby gain an extra 50 seats in the 300-seat parliament, "but we will be a strong power".

This may well be the shape of things to come after today's election. New Democracy and Pasok might win a majority, but they will face a social explosion if they try to cut earnings and raise more taxes. Syriza might come out ahead but will have difficulty creating a governing coalition. A more likely result, going by official polls, is New Democracy, slightly in the lead, forming a weak coalition with smaller parties. This probably would not last more than a few months.

Unless there is an unexpectedly decisive result today, Greece faces a political as well as an economic crisis. Any future government will be either unwilling or unable to implement reform or austerity. New Democracy supporters are hoping that having Syriza as a frightening alternative government may loosen purse strings in Brussels and Berlin, just as the Communist threat was once exploited by Greece to extract aid from the US.

There is something in this, but probably not a lot. Mr Tsipras is not Lenin and Syriza is not the Bolshevik party. Surprising though the party's swift rise from 4.6 per cent of the poll in 2009 to 16.8 per cent last month may have been, the fearful reaction of the Greek political and financial establishment and their counterparts in the outside world is surely exaggerated. Their overreaction may be a sign of their own sense of vulnerability after a prolonged economic crisis they are unable to end.

A problem for Greece is that a country with 11 million people and a tiny economy may be small enough to fail in the eyes of the rest of Europe. Its bankruptcy would not be the national equivalent of the collapse of Lehman Brothers. Mr Tzogopoulos fears that, on the contrary, Germany and the leaders of the EU could easily decide "to sacrifice Greece and go ahead with tighter fiscal union".

As for the election tomorrow, Greece will be lucky if a government emerges with enough popular support to take serious decisions of any description.