Austria's opposition Social Democrats appear to be headed for a narrow upset victory in Sunday's general election.

With all but the absentee ballots counted, the Social Democrats have won 35.7 percent of the vote with Chancellor Wolfgang Schuessel's ruling People's Party winning 34.2 percent.

Final results are to be announced next week.

Pre-election polls showed the People's Party slightly ahead.

Social Democratic leader Alfred Gusenbauer is expected to become the next chancellor, but would have to form a coalition government with the People's Party or another runner-up.

The far-right anti-immigrant Freedom Party and the Greens each won about won 11 percent of the vote.

Another rightist party, the Alliance for Austria's Future - which governs with the People's Party in a controversial coalition - won a little more than four percent.

Some information for this report was provided by AFP, AP and Reuters.