Republican presidential debates: Donald Trump leads in polls, but will his rivals risk attacking the billionaire in an attempt to move ahead?

GOP hierarchy refuse to rubbish reality TV star's campaign and admit he appeals to a dissatisfied electorate - but hope all ten candidates take aim at Hillary Clinton rather than each other

Trump card?: The business mogul will hope that his skills as a TV personality will stand him in good stead for the debate (Getty Images)

The lucky ten Republicans picked for Thursday night’s first presidential primary debate at the Quicken Loans Arena in Cleveland, Ohio, might note the giant basketball hovering over a side entrance. To stand out in this crowded field, they’ll each need to score a slam-dunk. Or should they make that a slam-Trump?

This may be the first in a long series of primary debates, yet the build-up was fraught with rare agitation. It was late on Tuesday that the main hosts, the Fox News Channel, did as they promised, naming the ten who had made the cut in recent polls to take part. They discarded seven others – it was a bad night to be called Rick – who will be relegated to a runners-up debate four hours earlier which few will watch.

Mr Trump, who knows something about reality competitions, is, of course, in. Moreover, because he is topping all the current polls and has recently even extended his lead, he will be bang centre on stage, possibly wearing his favourite ‘Make America Great Again’ cap. Immediately to his left and right will be Governors Jeb Bush and Scott Walker, who are tussling for second place in the polls.

Chris Christie and John Kasich, governors both (the latter of Ohio, where we are) won spots by the skins of their teeth. Two candidates from four years ago have been sent to the second stream, however: Rick Perry, who famously gaffed in a debate in the last cycle, and Rick Santorum. Bobby Jindal, Carly Fiorina, Jim Gilmore, George Pataki and Lindsey Graham are similarly humiliated.

Officials with the Republican National Committee (RNC), which is also holding its summer meeting here in town this week, hope the blessed ten will take aim more at Hillary Clinton, the putative Democrat nominee, rather than at each other. Mr Trump, who has won attention by being nasty, to Mexican immigrants and Senator John McCain mostly, promised that he’d be nice during this debate. Maybe.

“Certainly I don’t want to attack. If I’m attacked, I have to, you know, do something back, but I’d like it to be very civil,” he told ABC television. “I don’t want to attack anybody; you know, maybe I’ll be attacked and maybe not. I’d rather just discuss the issues.”

Yet the 5,000 ticket-holders arriving at the arena, its outside area spruced up by city crews power-washing pavements and painting flag-poles, won’t necessarily want candidates to dive deep into the minutiae of those topics. They and the millions watching from their homes will be agog for that slam-dunk moment. The great put-down of one rival by another. The joke that they instantly connect with.

Attacking Mr Trump will carry risks. Fox News is putting him in the middle because his average poll rating is 23.4 per cent. His nearest rival is Mr Bush with 12 per cent. If they still dare hope Mr Trump’s fans will eventually desert him, to which among them will they go? Even the RNC was anxious to dispel any notion it considers the Trump candidacy an embarrassment.

“People are upset with government, I think they’re upset with both parties... Donald Trump’s tapping into that,” Reince Priebus, RNC chairman, told CBS, even suggesting his big showings are “quite good for our party... what you’re seeing is a lot of people that were frustrated with politics are saying, ‘Well maybe I’ve got an outlet here’.”

Even with participants reduced to ten, each one will be lucky to get more than seven minutes of voice time in a debate that will run for two hours in prime time. Arguably under most pressure to make a fresh impact than anyone will be Mr Bush. Lower in the polls than many had expected, he startled many earlier this week at a pre-debate forum in New Hampshire, stumbling once more over a question about his family.

Among the seven at the tier-two debate at 5pm, the most livid with the arrangement appeared to be Mr Santorum. Fox News, he suggested, “need to apologise to the American public,” for excluding some of the candidates from the main event. “They’re the ones not getting the opportunity to get a chance see all the folks who could win this,” he said.

Presidential prowess? Republican party candidates in televised debate

Donald Trump

Mogul and presenter

Most likely to say: “You other guys are just a bunch of stiffs. I LOVE Mexico. I will make America great again!”

Least likely to say: “I invited Hillary Clinton to my wedding. Which wedding? I forget. Pass me a comb.”

Jeb Bush

Former Governor of Florida

Most likely to say: “I am the only one with a proven record as a conservative governor.” He will always add at least one sentence in Spanish.

Least likely to say: “I know how to campaign. The last time I ran for office? 2003.”

Scott Walker

Governor of Wisconsin

Most likely to say: “I took on the unions and beat them. I won two elections in a Democrat state and a recall election too.”

Least likely to say: “Put a guy without a college degree in the White House. I won’t tell you why I dropped out.”

Mike Huckabee

Former Governor of Arkansas

Most likely to say: “I will fight to end gay marriage and reverse the Supreme Court on Obamacare.”

Least likely to say: “You over there, Fox News guy. Keep my seat warm in the studio, because I’ll be back soon!”

Ben Carson

Former surgeon

Most likely to say: “Barack Obama has been a disaster for America and I am the only to have called him out consistently.”

Least likely to say: “I have never ever held elected office or even run for one. But I have a great life story!”

John Kasich

Governor of Ohio

Most likely to say: “Welcome to my state, where jobs are growing and spending is down. You want to win Ohio, don’t you?”

Least likely to say: “Don’t send me any foreign policy questions, because I’m more or less clueless. I might ramble. Again.”

Chris Christie

Governor of New Jersey

Most likely to say: “I am a two-term governor in a Democrat state with a record of reaching across the aisle.”

Least likely to say: “Any bridges in Cleveland I can foul up? Don’t ask me about New Jersey’s economy.”

Rand Paul

Senator from Kentucky

Most likely to say: “Everyone else on this stage is war crazy. I will not send your children to fight pointless wars abroad.”

Least likely to say: “Time Magazine called me ‘the most interesting man in politics’ last year. Why y’all yawning?”

Marco Rubio

Senator from Florida

Most likely to say: “President Obama is wrong on Iran and wrong on Cuba. I won’t chum about with tyrants.”

Least likely to say: “I look like a puppy, but bring it on Putin. Yes, Jeb Bush was my mentor. Who cares?”

Ted Cruz

Senator from Texas

Most likely to say: “I will end big government and slash Washington to ribbons. Bye-bye gay marriage and Obamacare.”

Least likely to say: “Hey, Mr Trump, if you want to play the ‘birther’ game again, I was born in Calgary, Canada!”