WASHINGTON - The Republican candidates for president are gathering for their third debate amid fresh volatility in an already chaotic race.
Retired neurosurgeon Ben Carson is surging past Donald Trump in Iowa and one-time front-runner Jeb Bush faces pressure to prove he's still a viable candidate for the GOP nomination.
Carson has been a low-key presence in the previous GOP debates, but he's likely to get more attention in Wednesday's debate after a series of preference polls show him atop the field in Iowa.
Trump has shown he's eager to take on Carson, jabbing him for his understated style and raising questions about his faith.
Meanwhile, Bush will be grasping for momentum after one of the most trying stretches of his White House campaign.