Polls have opened in Benin for an election to choose a successor to the West African nation's president, who is stepping down after two terms.

Citizens lined up Sunday to choose among 33 candidates vying for the position. The electoral commission says more than 4.7 million voters are expected at about 13,600 polling stations.

Benin's constitution imposes a two-term limit on presidential candidates. President Thomas Boni Yayi is not running, in contrast to some other African leaders who are changing their countries' constitutions to remain in power.

Favored candidates include Prime Minister Lionel Zinsou and Cotonou mayor Adrien Houngbedji. Businessman Patrice Talon, who made his fortune in Benin's main export of cotton, is also in the running. He went into exile in France, but returned in October.