One advantage he will have is that coming from a Democrat state he will be viewed as moderate or moderate/conservative and that will help him in the general election over whom ever the Democrats nominate who will be viewed as liberal. Coming from a position as moderate helps pick up the middle ground and softens a candidates positions they take on issues. It's not usually good to look so hard line. People like confident candidates to vote for but they don't like when someone supports issues that are seen as extreme.
Governor Mitt Romney has another advantage over all the other likely candidates so far. He is a governor and that helps him immensely. Going back many Presidential elections Governors have won many times. President George W. Bush, Bill Clinton, Jimmy Carter, and Ronald Reagan were all Governors first before being elected President. It's becoming almost necessary to be elected governor first to be a serious candidate for President and winning.
Take the poll, if you support Gov. Mitt Romney for President or is you don't think he would be good or elected. One thing is certain, Governor Mitt Romney will almost certainly be talked about and be a serious candidate for President of the United States.