The centre-right party headed by foreign minister Sebastian Kurz has won Austria's national election, putting the 31-year old on track to become Europe's youngest leader, the country's interior ministry said.
Interior Minister Wolfgang Sobotka said Mr Kurz's People's Party received 31.4% of Sunday's vote, a gain of more than seven percentage points from the 2013 election with counting nearly complete.
Mr Kurz described the jump in support as the greatest in party history.
The right-wing Freedom Party came in second, with 27.4% of the vote.
The centre-left Social Democratic Party of Austria, which now governs in coalition with People's Party, got 26.7%.
The results put Austria on track for a rightward turn.
Both the People's and Freedom Parties campaigned on introducing tough measures to curb immigration and to pressure foreigners already in the country to integrate.
The two parties will likely form the next government coalition.
Much of the People's Party's appeal has been credited to Mr Kurz, the foreign minister.
Since taking the helm in the spring amid growing strains within the governing Social Democratic-People's Party coalition, he moved his centre-right party further to the right, particularly on the issues of migration and Muslims.
But he avoids the inflammatory rhetoric of the right-wing Freedom Party and its head, Heinz-Christian Strache.
That made Mr Kurz's party appealing to voters who are uncomfortable with the Freedom Party but sensitive about immigration as large numbers of mostly Muslim migrants have entered Europe since 2015
Mr Strache modified the tone of his message and the party is keen on shedding its past links to anti-Semitism.
But it continues to attract a small neo-Nazi fringe.
Mr Kurz, greeting supporters as he cast his vote, said he hoped for "a good result, so that real change can be possible".
Expressing optimism at another polling station, Social Democratic Chancellor Christian Kern said "we are planning a longer party".
Mr Strache voiced optimism for "a good result and the chance for real change."
Left-leaning president Alexander Van der Bellen, who narrowly defeated a Freedom Party candidate in elections last year, said he "puts great value on pro-European government".
Mr Van der Bellen must swear in any new government and a strong showing by the Freedom Party and the People's Party would make a ruling coalition between them likely.
More than 6.4 million Austrians were eligible to vote.
Final results were not expected until later this coming week, when the last of the absentee ballots and ballots cast at polling stations outside a voter's district are counted.