Instead, there are hundreds of Republican candidates who have to win election on their own (as opposed to the party-list of other democracies, like Italy and Israel, or the party-centric elections of the Westminster model). And given the choice between jeopardizing their own jobs or breaking with the president, I can't think of any senators who would not choose the latter unless the president was acting out of some deeply-held principle the senator happened to share.

And that, to put it lightly, doesn't seem to be the case: The whole Miers nomination seems like a joke, the consequence of a faulty vetting process rather than the product of sophisticated calculation. And if senators are motivated by pure self-interest, going against the president's wishes on this matter is a no-brainer.

Incidentally, Hewitt is wrong to say that the absence of an anti-Miers champion in the Senate proves Republican support. It is likely that the Republican majority will try to soft-pedal this until Miers, voluntarily or not, withdraws her own nomination after suffering a thousand cuts. Similarly, the lack of a grassroots campaign to defeat Miers is not conclusive evidence that Republicans really, really like her; if they did, they'd be organizing under the leadership of the activist core of the conservative movement. But it is precisely the demoralization of those activists--not just commentators--that has resulted in the relative inactivity of the base.

For empirical support for my position, see this excellent Wall Street Journal position, which fully supports my earlier diagnosis of the Miers case.