The National Intelligence Estimate arguing that Iran gave up its nuclear-weapons program back in 2003 went public two weeks ago, instantly lessening the urgency of the domestic debate over how to handle Iran. The next day, Rudy Giuliani released a get-tough-on-Iran television ad, a pre-NIE message for a post-NIE world.

It's just one of the ways that Giuliani's once-formidable front-running campaign has been off lately. He has been buoyed all year long by his post-9/11 celebrity, his strong debate performances and his outsized, tough-guy persona. The former New York City mayor has undeniable leadership qualities, but now, as the primary race gets more serious, is having trouble making them fit the party he aspires to lead.

Giuliani is finally suffering from the natural gravitational pull of his messy personal life (as mayor, he had a publicly financed security detail for his mistress) and his ideological heterodoxy (especially on social issues). The pull has long been there; only now it has dragged him down to a level where it is no longer an invisible force.

Nationally, his numbers have been on slow downward slide since March. He was at 44 percent in an ABC News/Washington Post poll in February, and at 25 percent in the same poll last week. His lead over Mike Huckabee in the RealClearPolitics average of national polls is a mere two points. Hillary Clinton has a bigger leader over the second-place Barack Obama (30 points) in the latest ABC News/Washington Post poll than Giuliani has over the last-place Ron Paul (22 points).

This has trashed the Giuliani theory of the race, which was that his national lead in the polls was a bankable commodity that he could redeem even after losses in the early states of Iowa, New Hampshire, Michigan and South Carolina. It turns out that his national lead hasn't even survived the media attention that has gone to the hot candidate in Iowa, Mike Huckabee, weeks before anyone votes. What happens when Giuliani's competitors begin actually winning the early contests, with the attendant crush of attention and buzz?

Rudy had his eye on one of the early states, New Hampshire. His supporters thought once he started advertising there he'd bump up in the polls. Since Nov. 10 he has spent more than Mitt Romney and John McCain in the state, and his numbers have, if anything, declined slightly. McCain has passed him for second in the RealClearPolitics average in the state, and he hasn't gotten out of the teens in any poll since late November.

The nature of the ads has something to do with it. Besides the ill-timed Iran ad, Giuliani ran a spot touting his (truly extraordinary) work as New York City mayor. But Giuliani left the mayor's office six years ago, and was first elected -- and began the city's turnaround -- 14 years ago. Voters don't just want to know what you've done lately, but what you'll do for them in the future.

Over the weekend, Giuliani went to Florida to try to relaunch his campaign with a speech focused on his forward-looking "12 commitments" as president. He didn't mention the one about reducing abortions. When Giuliani was high in the polls, pundits speculated that the war on terror was the new social issue, more important to Republican voters than abortion or gay marriage. Huckabee's rise shows that social conservatives are still animated by their traditional issues, and Giuliani has little to say to them.

It's possible that the Republican field stays fragmented enough that Giuliani can win Florida on Jan. 29 and the big states where he is still strong on Feb. 5. But his scenario depends on a fractured party that he will have trouble putting back together again given his fundamental disagreements with a large part of the GOP base. In Florida, Giuliani said: "I don't just pray for miracles. I don't just hope for miracles. I expect miracles." He might have to.