He told USA Today he is running, according to Richard Cowan of Reuters. But sources close to Fred Thompson are saying The Politico's Mike Allen got it wrong by reporting he will announce on the 4th of July in Nashville.

Thompson has asked to be released from his role on Law & Order, and opened an "exploratory committee" which allows him to raise money without formally declaring, both of which seem to indicate he will get in.

Ever since the Thompson rumors started a couple of months ago, I've maintained he was waiting to see if McCain's candidacy imploded. While McCain isn't inclined to get out, most of the news (saving the ARG polls which always seem to show him running stronger than all of the other polls) for him has been bad. He came in a dismal third among Republicans in the critical first quarter fundraising, sixth among major candidates if we count the Democrats. His immigration reform collaboration with Ted Kennedy is widely reviled by the GOP base.

McCain's polling in most states has been either flat or declining, and even the favorable ones suffer by comparison with 2000. For example, his ARG numbers of 30% in NH and 25% in SC are higher than any other poll finds for him, yet in 2000 he won 49% of the vote in NH and 42% in SC as the challenger. As one of the putative frontrunners and the "next guy in line" in the GOP (which tends to nominate the "next guy in line"), his numbers have declined by nearly 40% in NH (from 49 to 30) and and SC (from 42 to 25). Not exactly a sign of a campaign on the move . . .

Thompson has left himself just enough wiggle room to stay out if McCain comes in with strong second quarter fundraising, but another sixth place finish will almost certainly spell doom for the Arizona Senator's campaign, Thompson or no Thompson.

Who gets hurt the most by Fred getting in?

First of all, Tommy Thompson, who has undoubtedly enjoyed his sporadic poll successes due to confusion with the Tennessean. McCain, of course, because he cannot stand another credible candidate in the race. Romney has been steadily improving his position, but by inches, not miles, and Fred Fever has already had an impact on his momentum. Giuliani suffers, too, because Thompson can project the strong image like Rudy and McCain do, without their negatives in other areas.

It will certainly shake up the race. Will Thompson be able to garner more support as a declared candidate than as a wistfully imagined one? Can he put together enough organizational talent, given the many qualified people already committed to others?

I'm also hearing that Newt Gingrich is leaning strongly towards entering the race as well. He never draws very high numbers, usually in the high single digits, but those he does attract are strongly conservative - the very folks everyone else is having trouble securing.

If both of them get in, why should McCain get out, though (unless his fundraising was really in the toilet)? The race would be completely up for grabs. Considering both parties, there hasn't been a more competitive year since 1968 . . . if Bobby Kennedy hadn't been killed, the Kennedy-McCarthy-Humphrey battle at the convention would have been the focus of attention, not the protests. And if George Romney hadn't used the wrong word - had he said "they showed me what they wanted me to see" instead of "brainwashed" - and if Ronald Reagan had jumped in earlier, the GOP might still have nominated Nixon (who had spent years quietly raising money for local and state parties and candidates), but it wouldn't have been a coronation.

Is it truly a curse to "live in interesting times?"

Whatever happens, it is useful to compare the potential fields. The GOP top five would include Giuliani, McCain, Romney, Thompson, and Gingrich. The Democrats' would be Hillary, Obama, Edwards, Richardson, and Biden. There is a major "gravitas" gap there. Thompson is the Republicans' weakest candidate in terms of relevant experience, and yet only two of the Democrats can claim greater experience than he - Richardson and Biden - and neither of them has a practical chance of winning.