Mitt Romney did not win the Republican nomination tonight, but he showed why he’s the likely nominee. All along, we’ve known that Romney had significant vulnerabilities as a candidate, but also had a lot of money and a strong organization. Yet in early states where retail campaigning plays a more important role, his organizational advantages could only get him so far. Rick Santourm edged him out in Iowa despite having virtually no campaign and in South Carolina, Newt Gingrich came back from the dead on the back of strong debate performances. But Florida, a state that’s spread apart with several large media markets, is not a retail campaigning state. And thus, it’s a much better test of what the campaign will be like as it goes national, when candidates will have to fly around to campaign in multiple states, and rely on television ads to get their message out. In Florida, Romney passed the test with flying colors.

Romney’s strong organization helped him bank a big chunk of votes from those voting early. He also outspent his rivals overwhelmingly, with a blitz of attack ads that drove up Gingrich’s negatives. Going forward, the race will be fought along these lines. It will be hard for Santorum or Gingrich to catch Romney with retail/grassroots style campaigning, there are now fewer debates spread out over more time, and they’ll get less national media attention.