Turkey will hold nationwide local elections on Sunday March 31, but the headline contest by far will be in Istanbul where Ekrem Imamoglu—the politician who dented President Recep Tayyip Erdogan’s aura of invincibility in 2019 by defeating the ruling party candidate to win the mayorship of the cultural and economic capital—will attempt to win re-election. Voters of the pro-Kurdish DEM party (previously known as the HDP party) were five years ago crucial to that win, which saw them lend Imamoglu their votes, as the main opposition CHP party candidate shocked Erdogan and ended a quarter century o…