Candidates in some of the most contested Senate races have found something to agree on — giving President Barack Obama the authority he's asked for to train and arm Syrian rebels taking on brutal Islamic State militants.

Democratic congressman Bruce Braley and Republican opponent Joni Ernst, battling for a Senate seat from Iowa, are in agreement. So are opponents in Colorado, incumbent Democratic Sen. Mark Udall and Republican congressman Cory Gardner.

Opposing the commander in chief on a question of fighting terrorists poses risks for candidates in tough races in November. Yet standing with an unpopular president seeking to broaden a dangerous conflict carries hazards, too.

Some Senate challengers avoid questions on the topic, while at least one endangered Democratic incumbent, Sen. Mark Begich of Alaska, plans to vote "no."