Thompson has acknowledged that he has raised his own stakes by waiting so long. He told the Web site Politico.com in an interview this week that he should be judged by the standards of previous campaigns, where declaring the fall before the election was more typical.
"Historically, people don't get in this soon," Thompson said. "The question is about the fact that everybody else is out there and [they] have spent all this time and all this money — and I still clearly have a shot. That ought to answer that question in and of itself."
Indeed, national polls have generally shown Thompson running second in the Republican race, behind former New York Mayor Rudolph Giuliani. A Gallup poll released Aug. 16 had Giuliani at 31 percent and Thompson at 16 percent — ahead of former Massachusetts Gov. Mitt Romney and Sen. John McCain, R-Ariz., both of whom have been essentially running for president since last year.
But state polls in Iowa and New Hampshire haven't been as promising for Thompson — a function, most likely, of his slow start in organizing in those politically active states. And the drifting nature of his pre-campaign has added fuel to long-standing questions about Thompson's work ethic.
"All this disarray, it's more telling for Sen. Thompson than it would be for other candidates, since he doesn't have any executive experience," Ayres said. "He is going to be judged as an executive by the way he organizes and executes his campaign."
He's also given other social conservatives — notably former Arkansas Gov. Mike Huckabee — room to build on their candidacies. Huckabee this week blasted Thompson, telling the Christian Broadcasting Network that he has "no substantial record" from his time in the Senate.
"I think a lot of it is that people aren't sure whether they're electing a former senator or Arthur Branch," Huckabee said, referring to the character Thompson played on "Law & Order."
"Anytime a person [who] is on television a lot and a celebrity, there's a sense in which people are given a unique pedestal on which to stand, and it's the celebrity more than it is anything — the attention that comes from that and the sort of gee-whiz factor and, 'I've seen him on TV,'" Huckabee said.
Thompson should know pretty quickly after he gets in whether he's already peaked, Reynolds said. And it's possible that the actor has been playing his role just to build anticipation.
"There's a plausible story where what he's doing is a masterful rope-a-dope," Reynolds said. "But for that to be true, he's going to have to come out fighting."