Campaign dynamics change quickly, but the day after the Bloomberg/Washington Post debate Mitt Romney, the former governor of Massachusetts, towers over a field of Tea Party ankle-biters who may continue to harass him as he marches toward the nomination, but who don’t offer a credible alternative. Let us count the ways Romney is now solidifying his place as the G.O.P. frontrunner:

The Establishment

One of the great sub-dramas of the Republican primaries has been the dissatisfaction of the party’s donor and opinion classes with the options at hand—Romney’s bland but seemingly inevitable candidacy, or an unelectable right-winger—and their hunt for someone to rescue the Party. The list of draftees who have declined to run is familiar: Jeb Bush, Mitch Daniels, Paul Ryan, Chris Christie. Christie, who has a flair for the dramatic, ended this chapter of the campaign last week with a fifty-minute press conference shown live on the cable news channels. Christie loyalists headed to Romney, and yesterday Christie himself endorsed him. The white-knight phase of the campaign is now over. Fox News and the opinion pages of conservative media have exhibited a noticeable shift from attacks on Romney to a muted resignation about his candidacy. The party is gradually accommodating itself to him.

The Perry Implosion

Romney has been running for President for years, while Rick Perry has been running for a few months. The debates have magnified this difference in preparation and polish. Various theories have been put forward for Perry’s embarrassing debate performances—back pain, not enough sleep—but by now we’ve seen enough to know that Perry is simply inarticulate, has trouble making arguments, and is lost once the conversation turns to issues outside of the ones he mastered as governor of Texas. He entered the Presidential race late; he has not spent time preparing for the office, and it shows. These might be forgivable sins in a Republican primary—George W. Bush was hardly a great communicator—but Perry also got on the wrong side of the immigration debate for conservatives and gave a weak response to Romney’s sustained argument that Perry’s views on Social Security made him unelectable. Conservatives have little incentive to mount an aggressive defense of an already damaged candidate.

The Others

Choose your condescending analogy: the seven dwarfs, Lilliputians, the Cantina scene from Star Wars. Romney’s other opponents are a ragtag collection of defeated candidates from a previous era (Rick Santorum, Newt Gingrich), extremist House members (Ron Paul, Michele Bachmann), a motivational speaker never elected to office (Herman Cain), and a successful governor and diplomat despised by his party (Jon Huntsman). Bachmann and Cain have each experienced a temporary surge in the polls. Bachmann’s came and went in August, while Cain is peaking now. Nobody should be surprised if Gingrich and Santorum each have their own moment in the spotlight as well. What seems to be going on is that the large pool of anti-Romney conservatives has been sloshing from one right-wing candidate to another while never finding a permanent home. In the meantime Romney’s support has remained remarkably consistent. (To see a visualization of this phenomenon watch Slate’s “horse race” animation of the campaign.) The longer these fringe candidates remain in the race, reducing the likelihood that the anti-Romney vote coalesces around a single person, the better Romney’s chances become.

The Right Formula

At the beginning of the campaign, a great deal of commentary focussed on Romney’s biggest liability: the fact that his Massachusetts health-care plan served as the model for Obama’s national plan. Some argued that this disqualified Romney from the nomination. Romney’s heresy seemed debilitating in a vacuum, but not once he began to be measured against his opponents, with all their idiosyncratic flaws. Republicans will nominate the person who has the best mix of electability and conservatism, and right now, despite his health-care plan, Romney has that formula mastered better than his rivals.

Photograph by Daniel Acker/Bloomberg via Getty Images.