If Christie has a base, it consists of Wall Street donors, a media fascinated by his persona and relative moderation, and some but by no means all members of the non-tea-party-wing of the Republican Party.

He does not have the committed ideological core that Ronald Reagan could rely on to overcome Iran-Contra. He does not have the Democratic base that stuck with Bill Clinton during his sex scandal because the excesses of a special prosecutor and then of a Republican House that impeached him came to enrage Democrats even more than Clinton’s misbehavior.

What of Christie’s base? Wall Street is fickle and pragmatic. The media can turn on a dime. And the Republican establishment, such as it is, has alternatives. Oh, yes, Christie also has support from some machine Democrats in New Jersey who have made deals with him. But they will be even more pragmatic than Wall Street.