Austrians are voting in a re-run of a presidential election which pits the leader of the far-right Freedom Party Norbert Hofer against former Green Party head Alexander Van der Bellen, BBC reports.
The vote last May was narrowly won by Mr Van der Bellen, but the result was overturned by Austria's highest court because of irregularities in the count.
If Mr Hofer wins, he will become the EU's first far-right head of state. Opinion polls held in November suggest the vote is too close to call.