E. J. Dionne Jr. thinks so:

First, compared with Palin, Romney is a plausible president. . . .
Second, Romney is a kind of front-runner for the 2012 Republican Presidential nomination, and Palin’s huge presence in the media blocks out alternatives to Romney. . . .
Third, I am absolutely convinced that Palin will not run for president, but that it’s in her interest not to say so until the very last moment. . . .