Polling is close ahead of Turkey's elections Sunday

Turkey holds presidential and parliamentary elections on Sunday.

Retired civil servant Kemal Kilicdaroglu is running about even in the polls with President Recep Tayyip Erdogan. Erdogan has been leading the country for two decades, and many see Sunday's election as the biggest challenge to his power yet.

Here & Now's Celeste Headlee speaks with Onur Isçi, assistant professor of international relations at Bilkent University in Ankara.