Voters in France are choosing between Francois Fillon and Alain Juppe to be their centre-right presidential candidate in next year’s election.
Mr Fillon is now seen as the favourite to win Sunday’s run-off, after securing 44.1% of votes in the first round a week ago. Mr Juppe had 28.5%.
Former President Nicolas Sarkozy was knocked out of the race.
The Republicans candidate is widely expected to take on far-right National Front leader Marine Le Pen next spring.