PHOENIX, AZ - JULY 11: Republican Presidential candidate Donald Trump...

PHOENIX, AZ - JULY 11: Republican Presidential candidate Donald Trump addresses supporters during a political rally at the Phoenix Convention Center on July 11, 2015 in Phoenix, Arizona. Trump spoke about illegal immigration and other topics in front of an estimated crowd of 4,200. (Photo by Charlie Leight/Getty Images)

I can't help thinking of the great 1995 Chicago Bulls bench when looking at the names of the Republican presidential candidates who didn't make the cut for Thursday's prime-time Fox News debate.

Each of them would be a starter in any other contest: Louisiana Gov. Bobby Jindal, South Carolina Sen. Lindsey Graham, former Texas Gov. Rick Perry, former New York Gov. George Pataki, former Hewlett-Packard chief executive Carly Fiorina, former Pennsylvania Sen. Rick Santorum, and former Virginia Gov. Jim Gilmore. Yet, in this surreal political environment, they've all been relegated to the backbench -- to Thursday's 5 p.m. warm-up show.

Collectively, this has to be the strongest GOP field in a half-century. It's certainly the largest. But in a bizarre sign of the times, it's at the same moment weak enough that Donald Trump is leading it. That's how tired the voting public is of "establishment" politicians.

With Trump in the main debate Thursday, the undercard fight may very well turn out to be the more substantive forum. But it will draw a fraction of the viewers. Most eyes will be tuned in to the 9 p.m. show to see Trump tussle with former Florida Gov. Jeb Bush, Wisconsin Gov. Scott Walker, neurosurgeon Ben Carson, former Arkansas Gov. Mike Huckabee, Texas Sen. Ted Cruz, Florida Sen. Marco Rubio, Kentucky Sen. Rand Paul, New Jersey Gov. Chris Christie, and Ohio Gov. John Kasich.

Who would want to miss that bit of prime-time reality TV?

The relative few who watched the St. Anselm College forum earlier this week were treated to impressive and substantive two-hour round of political speed dating. Jack Heath, the New Hampshire radio host and the forum's moderator, did a masterful job tailoring questions to each of the candidates.

I just wish Trump would have attended so Heath could have questioned him one-on-one, too. I suspect Heath would have asked Trump a question many people probably want answered: "Is humility an essential quality for an American president?" I'd pay to hear Trump's response.

No one knows how The Donald will behave Thursday night. But his presence in the debate alters it before it even begins. It turns a great American educational forum into a 21st Century entertainment venue. How many millions will be tuning in just to see whether Trump makes a mockery of the stage? How many are hoping he does?

What I'm hoping is that Trump tones down his act Thursday. I'm praying his advisers have convinced him that he has an actual shot at the presidency. Because once Trump gets serious -- once he begins answering questions truthfully and in detail -- he'll sound just like the others, only far less talented.

He'll be lucky to make the next 5 p.m.

William F. B. O'Reilly is a Republican consultant.