Sarah Palin is a populist and such people scare the hell out of political hacks like Rove who make a living as Washington DC parasites.
No doubt some Republican elites don't want to see upstarts gain so much influence, and the Rove ego and self-importance doubtless make it that much more difficult for "The Architect".
(I wish someone would slap Hannity every time he uses that term for Rove. Rove was the architect of the Republican nose dive from 2004 through 2008.)