I consider it a banner day when I can render my friend Ann Coulter speechless.

The wonderful conservative warrior was a guest on my radio show this week (Ann is one of the best guests in the business) and I hit her with something so wild, so preposterous, and so outrageous, that she just, well, stayed silent for a few seconds.

After a long pause, she laughed and said, “You know, he’s just stupid enough that he might do it!”

The “he” in question is Sen. John McCain. Ms. Coulter has made no secret of her total and utter disdain for the GOP presidential candidate. To many diehard conservatives, Sen. McCain is that horror of horrors, a Republican with enough moderate tendencies as to attract people to him who might not ordinarily vote for a Republican.

So I thought I’d have some fun by sharing with her a prediction that one of my radio callers made earlier that day.

When the caller, Tim from Atlanta, first suggested it to me, I had virtually the same reaction as Ann. I was stunned.

“Mike”, he started. “Something came to me last night while I was watching the TV coverage of the primaries in Indiana and North Carolina. I was wondering just who John McCain might pick as a running mate and it hit me like a ton of bricks: I predict that after Hillary is finally forced out of the race, McCain will shock the world and pick Hillary Clinton as his vice-presidential candidate!”

Think about that for a minute. “McCain/Clinton 2008.”

After I pulled myself off the floor and sat back down in my chair, I asked Tim from Atlanta how that idea could possibly have any merit.

“It’s simple”, he replied. “The media keeps beating the drum about bi-partisan cooperation in Washington in order to get things done. People continue to harp about being tired of all this bickering and politicking and fighting. McCain is well known for wanting to reach across the aisle and work with Democrats – who could forget McCain/Feingold – and it’s pretty much understood that Madame Hillary would do just about anything to get back to the White House,” he said. “A McCain/Clinton ticket would be virtually unstoppable!”

The only thing stopping right now is the beating of my heart at the prospect of such a nightmare.

But his prediction demonstrates just how loopy this entire campaign cycle has become. It also reinforces the heartburn and headaches that many of us Republicans are experiencing as we get nearer and nearer to the general election.

Writer David Frum believes that John McCain is possibly the perfect GOP candidate in an ever-changing country. Frum, a daily contributor to National Review Online and best-selling author, thinks it’s a huge mistake for us to pine for the days of Ronald Reagan-era conservatism. He argues that a successful Republican presidential candidate will be the sort of person who demonstrates unshakable integrity, a willingness to shake off some of the previous conservative orthodoxies, and can challenge and even disagree with some of the cultural philosophies that helped define the Reagan Revolution. Frum makes the case that a successful GOP candidate will be the one who returns to fiscal conservatism, reigning in out-of-control spending, even if he or she wanders off the reservation over an issue like illegal immigration.

That view, of course, is heresy to a rock-ribbed conservative like Ann Coulter. In fact, when I asked her about Frum’s arguments, she chortled and admonished me to stop asking her about people like David Frum “who aren’t real conservatives.”

I greatly admire the torchbearers of conservatism like Ann and Rush Limbaugh and others who believe that the real peril is in Republicans even considering moving one inch to the center.

But David Frum is a smart guy, too. He makes a compelling case that if the GOP has any chance of retaining power in D.C., the party should realize that this isn’t our father’s Republican Party anymore. Instead of hearing all the supposed stories of Republican voters willing to support Barack Obama (a bizarre concept that I still can’t understand), why not produce a GOP candidate that Independents and even Democrats can support?

He seems to think McCain might be that guy.

Whichever point of view you endorse, it seems pretty evident that as Sen. McCain prepares to gear up for a full scale battle during the next six months, the Republican Party is at a crossroads.

Let’s hope Sen. McCain doesn’t choose to cross the road hand-in-hand with Sen. Clinton.