CLEVELAND - The Republican bid to reclaim the White House begins in earnest Thursday with the first debate of the 2016 campaign, a 10-candidate face-off for leadership of a party grappling with internal divisions and a changing American electorate.
Taking center stage for the prime-time debate in Cleveland was Donald Trump, the billionaire businessman whose summer surge has upended the Republican field. With an unpredictable style and unformed policy positions, Trump is a perplexing foe for his GOP rivals.
Joining Trump on stage in the important election swing state of Ohio was a field of seasoned governors, rookie senators and a never-been-elected outsider.
As in the 2012 Republican primaries, the GOP faces a tug of war between those eager for a candidate with broad general election appeal and those who think the key to winning is nominating a fiery conservative.
"You're starting off with a lot of candidates who have an initial group of support that reflects a particular element of the party, but nobody is close at this point to putting together a majority coalition," said David Winston, a Republican pollster.
While 17 Republicans are seeking the party's nomination, only 10 were invited by debate host Fox News to participate in the main event. The remaining seven were relegated to a pre-debate forum, a low-key event in a largely empty arena, where candidates avoided debating each other and largely stuck to scripted responses on domestic and foreign policy.
Former Texas Gov. Rick Perry and businesswoman Carly Fiorina opened the early event with biting criticisms of Trump.
Perry - whose failed 2012 White House campaign was damaged by an embarrassing debate stumble - accused Trump of using "his celebrity rather than his conservatism" to fuel his run for president.
Fiorina, the only woman in the GOP field, said that Trump had tapped into Americans' anger with Washington, but she challenged the businessman as lacking policy positions. "What are the principles by which he would govern?" she asked.
While the candidates pitch their visions for the Republican Party's future, they'll also be making the case that they would present the strongest general election challenge to Hillary Rodham Clinton, the front-runner for the Democratic nomination.
Clinton was scheduled to be traveling during the debate and didn't plan to make a statement afterward. Her campaign preemptively made the case that there was little difference between Trump's "outrageous" positions and the rest of the field.
"They all have an identical agenda," said Joel Benenson, Clinton's chief strategist.
Trump's Republican rivals have spent the summer grappling with how to manage his unexpected popularity. With a populist message and outside-the-Beltway resume, he appears to have tapped into voter frustration with Washington. But some Republicans fear his talent for outlandish comments - whether about Mexican immigrants or the war record of Arizona Sen. John McCain - will taint the public's view of the party as a whole.
"A problem-solver that isn't a career politician is something that's appealing to many people," said Michigan Gov. Rick Snyder, a Republican. "But I would hope it could be done in the context of not being offensive to people."
Ahead of the debate, Trump said he didn't plan to attack his rivals. "I'd rather just discuss the issues," he said Wednesday on ABC's "Good Morning America."
Standing to Trump's left on the debate stage will be former Florida Gov. Jeb Bush, a favorite of the wealthy donors and business leaders who populate the establishment wing of the Republican Party. But like Mitt Romney, who filled that role in 2012 before ultimately claiming the nomination, Bush has struggled to break away from the rest of the field.
The son and brother of former presidents, he also faces questions about whether his nomination would mark a return to the past.
To Trump's right on the stage will be Wisconsin Gov. Scott Walker, whose victories over unions in his home state created his national profile. Florida Sen. Marco Rubio, the youngest candidate in the field at age 44, is trying to carve out a niche as a foreign policy authority, but has struggled to break through this summer - particularly since Trump's surge.
A host of candidates with sharply conservative records and attention-grabbing personalities are seeking to pull the party further to the right, including Texas Sen. Ted Cruz, surgeon and tea party favorite Ben Carson and former Arkansas Gov. Mike Huckabee, a popular choice among evangelicals and social conservatives. Kentucky Sen. Rand Paul adds a libertarian twist to the Republican field.
Rounding out the top 10 are two governors. New Jersey's Chris Christie is a past favorite looking to return to the top tier, while Ohio's John Kasich is a latecomer to the race whose first campaign for president 16 years ago never took off.
Thursday's debate is the first of six party-sanctioned forums scheduled before primary voting begins in February. Fox News used national polls to determine which 10 candidates would be on the stage, and several candidates were grouped together in the single digits - most separated by a number smaller than the polls' margin of error.