Bill Press is a syndicated columnist and the co-host of CNN's Crossfire, which airs Monday-Friday at 7:30 p.m. ET, and The Spin Room, which airs Monday-Friday at 10:30 p.m. ET.

Bill Press: Will McCain be next to jump ship?

WASHINGTON (Tribune Media Services) -- It must be the sun. That burning, glaring, searing, roasting, relentless desert sun.

It must be the sun that turns grizzled Arizona conservatives into huggable moderates.

Look what happened to old Barry Goldwater. He was transformed from a Cold War fanatic, wanting to lob a nuke into the men's room of the Kremlin, to a New Age radical, openly supporting gays in the military.

And now look what's happening to John McCain. He's gone from the favorite son of Republican conservatives to the wayward son -- even poking a finger in their eye by inviting top Senate Democrat Tom Daschle to spend the weekend at his ranch near Sedona.

"Purely social," says McCain. But chances are they talked about more than whether gas-fired or charcoal grills give ribs a better flavor. In fact, chances are they talked about Tom Daschle's plans as new Senate majority leader and how he and McCain might work together.

Is there a chance they also talked about Jim Jeffords? Did McCain admit over beer and barbecue that he, too, is unhappy in the Republican Party? Could he be the next Republican Senator to jump ship? That prospect worries every Republican. It worries George W. Bush so much he finally got around to inviting John McCain to dinner at the White House. This week. Five months late.

For McCain, it must be tempting. He's never been a party hack. He cares more about policy than partisan politics. And when he looks around at the issues he cares about, here's what he sees: on campaign finance reform, he's teamed up with Democrat Russ Feingold; on tighter controls on gun shows, with Democrat Joe Lieberman; on the patients' bill of rights, with Democrats Ted Kennedy and John Edwards; on tax cuts, with Daschle.

At the same time, his Republican colleagues are fighting against him on each and every one.

Why not make it official? Why shouldn't McCain become a Democrat? Wouldn't he be better off walking away from his enemies and joining forces with his friends?

The answer is: no. McCain shouldn't become a Democrat for one good reason: He has a lot more clout right where he is. After his spectacular success in the primaries, he enjoys a huge and loyal national following.

As a maverick Republican, willing to work across the aisle on legislation, he is treated like a king by hopeful Democrats. And, as a dissatisfied Republican, who might any minute walk away, he is romanced by nervous Republicans.

He's got everything going for him. Short of the White House, McCain will never have as much power. It makes no sense for him to change now.

And that's the key word: now. Timing is everything in politics. McCain's best move now is simply to wait. Wait and watch. Wait to see how well Bush does. Watch to see if he signs the McCain-Feingold legislation, supports a patient's right to sue HMOs or challenges the NRA on gun show loopholes. And, perhaps most importantly, watch to see if Bush ever wakes up to what's happening in other parts of the world and exercises his responsibility as world leader.

There's no doubt that John McCain, like most Americans, is less than impressed by Bush's performance on the job so far. If, three years from now, Bush continues to falter -- if he still hasn't proven up to the job -- if he's still governing as the captive of the far right -- that's the time for McCain to make his move. Then he will have not only the opportunity but also the moral obligation to challenge Bush for re-election.

In 2004, McCain has two options. He can run as a Democrat. Even if he switches parties at that late date, the party's nomination would be his for the asking. Or he can choose the tougher road and run as an independent. Either way, he could easily win.

George Bush doesn't have to worry about what John McCain will do this week. It's what John McCain might do three years from now that should keep him awake at night

Bill Press is Co-host of CNN's "Crossfire". His e-mail address is: Billpress@aol.com