Because the Republican brand is so much worse now, Christie will have to distance himself from it more dramatically than Bush did to win over Hispanics, young people, and to a lesser extent women. But he also will need to rack up huge margins from the Republican base, a group with whom he lacks Bush’s tight bond.

In 2000, it was much easier for Bush to keep the GOP’s right-wing base happy while still winking at swing voters. In the run-up to the Iowa caucuses, Steve Forbes, Gary Bauer, and Alan Keyes all tried to win over Christian conservative voters by talking nonstop about abortion and other red-meat cultural issues. Bush, by contrast, ignored those subjects almost completely, seeking to safeguard his reputation among general election moderates. Yet among Christian right voters in Iowa, Bush still came out on top. The reasons: his own, highly publicized evangelical faith, which he effectively advertised a few weeks before the caucuses by announcing during a Republican debate that “Christ” was his favorite philosopher. And he had strong support from Republican leaders—including Christian right leaders such as Ralph Reed—who mobilized conservative voters behind the candidate they thought could win in November.

Christie has neither of those advantages. He lacks Bush’s strong emotional connection with the Republican base, and compared to 2000, that base is far less willing to defer to pragmatic elites. A recent study by William and Mary researchers, for instance, found that three-quarters of Tea Partiers would rather back a Republican candidate they agree with on the issues but trails far behind the likely Democratic nominee than a candidate they agree with less who has a better chance to win.