"Add up the wealth of the last eight presidents, from Richard Nixon to Barack Obama. Then double that number. Now you're in Romney territory."
It should be noted that Romney would be in the top 1% based solely on the income he receives in one week.
But I think Steve Benen is right:
The problem isn't that Romney is extremely wealthy. It's hard to imagine a significant number of voters saying, "I'm uncomfortable voting for a rich guy."
The problem is how Romney acquired his vast wealth (a vulture-capitalist firm), his frequent gaffes on the subject, and his policy agenda (which includes more tax breaks for the wealthy).