SC Sen. Lindsey Graham tells The Hill that the former and still very popular Florida governor would be his pick.
“He’d be an outstanding pick. It’s up to Gov. Romney but if I had to recommend a single person it would be Jeb."
Generally, there are three problems with Jeb for Veep.
a. Even though the "Bush" name could genuinely deliver Florida for Mitt, it'd inject an unwelcome discussion of W's presidency and give the Obama campaign a supremely easy talking point -- that Romney is a return to the Bush years.
If Obama were able to effectively make that link (which he's already tried to do), it could help minimize Romney's current advantage on the debt and deficit.
b. A common fear is that Bush would overshadow Romney and/or that people would openly pine for Jeb at the top of the ticket, making Mitt look smaller and weaker. That's probably the very last thing a nominee wants from a Veep.
c. It's often thought that Jeb didn't run for president because he, ultimately, didn't think voters were ready for another Bush in 2012 and wanted to bide his time until the winds turned more favorable.
A Veep run might throw those efforts out the window by prematurely forcing a national discussion about what another Bush would mean for American politics.