VIENNA - Austrians began casting their votes for a new parliament Sunday, but the outcome was unpredictable with a quarter of Austria's voters undecided and far-right leader Joerg Haider's Freedom Party in freefall.

Chancellor Wolfgang Schuessel's conservative People's Party, which broke off an alliance with Haider in September, could see its strongest gains in decades but still wind up in opposition if Haider's party does not do well enough to form a coalition.

The leftist Social Democrats hope to return to power after nearly three years in opposition, either with the smaller Greens or in a repeat of the ``grand coalition'' with the conservatives that governed for 13 years until 2000.

The snap election was called after Haider triggered a coalition crisis by trying to retake control of the party he led for 15 years until 2000, forcing the resignation of moderate Freedom ministers. Schuessel then called off the coalition.

Haider drove through the morning fog in his dark blue Porsche Targa two hours after the 7:00 a.m. (0600 GMT) opening of polls to cast his vote in his home town of Klagenfurt, the provincial capital of Carinthia where he is governor.

Unlike Austrian political analysts who say Haider's party could lose as much as two thirds of its seats in parliament, the anti-immigration firebrand was optimistic.

``I expect a good result, one that leads to a stable development, and I hope that all the predictions from the recent opinion polls don't come true,'' Haider told reporters.

But one former Haider supporter expressed annoyance that he toppled the government and forced her to visit her local polling station a year ahead of next year's scheduled general election.

``I've gone back to voting for the conservatives,'' Klagenfurt pensioner Margarete Urban told Reuters.

``Last time I voted for the Freedom Party because they seemed to have the best line on cracking down on immigration. But they've become a fractious and divided party. They've lost all credibility for me,'' Urban added.

Marie Spitaller, a Klagenfurt nurse, was even more disgruntled.

``I'm very irritated with the current government,'' she said. ``There's no stability. They're all at each other's throats. I hope the Freedom Party loses hugely.''

But with the Social Democrats and People's Party both polling around 40 percent on the eve of the election, political analysts said it was impossible to predict the outcome.

``It looks like a real neck-and-neck race,'' said Peter Hajek of the Vienna-based OGM Institute.

``The two traditional partiesare heading for around 40 percent, and the Greens and Freedom Party are also neck-and-neck around 10 percent or maybe even less,'' Hajek told Reuters.

Austria's ailing economy, forecast to grow less than one percent this year with unemployment rising to over five percent, has been the focus of campaigning.

Polls close at 5 p.m. (1600 GMT), with the first exit polls due immediately afterwards on Austrian state television.

CLOSE RACE

Preliminary official results are expected as early as 7:30 p.m. (1830 GMT). With a close race expected, the counting of some 380,000 ballots from overseas and people traveling on election day could delay a final result for a few weeks.

Adding to uncertainty, pollsters said a record quarter of Austria's 5.9 million voters were still undecided a week ago.

While it could be weeks before a new government is settled, it is clear that Haider's anti-immigration, euroskeptic Freedom Party faces an electoral drubbing from voters who blame it for the government's collapse.

It won 27 percent of the vote in 1999 to become Europe's most successful far-right party.

Haider dominated Austrian politics for much of the 1990s, leading his party to a string of successes until it won second place in 1999 and formed a government with the People's Party.

But his popularity has waned since he quit as party chief in May 2000 after the EU and the United States imposed diplomatic sanctions on Austria over the far-right's entry to government.

The conservatives, the Social Democrats and the Greens all back the European Union's eastward expansion, suggesting there will be a comfortable parliamentary majority to ratify the move despite fierce opposition from the Freedom Party.