You'd think it would be the Democrats that would be hard on Romney

Nope. The tea party wants to stop him.

'“We have very little time to educate Republican primary voters on Mitt Romney’s real record—as a liberal who has fought against conservatives on just about every important issue facing America,” the fundraising appeal said'.
From : http://www.chicagotribune.com/news/nationworld/la-pn-stop-romney-20111005,0,51900.story