ANKARA, Turkey — Rather than toppling Turkey's strongman president, a failed military coup that left more than 250 dead appears to have bolstered Recep Tayyip Erdogan's immediate grip on power and boosted his popularity. Tens of thousands marched through the streets in half a dozen Turkish cities late Saturday, waving flags and singing songs in an emotional outpouring of support for the long-time leader as security forces rounded up military personnel it branded coup supporters and launched a purge of judges seen as government opponents. Prime Minister Binali Yildirim said the perpetrators of Friday's failed coup "will receive every punishment they deserve," and the government said it would take steps toward extraditing a U.S.-based cleric it accused of fomenting the uprising.