Bandwagon Effect

Rick Perry of Texas, a former Giuliani backer, has become the latest in the sudden series of Republican governors to endorse John McCain. This is more than anything further evidence of McCain's emergence as the GOP frontrunner.

These governors are playing a much different role from 2000, when every one of the nation's Republican governors endorsed Perry's predecessor, George W. Bush, early, helping to install him as the consensus "establishment" pick.