I guarantee that Obama will not get the nomination. While I would not bet on the Republican nomination, Clinton has this one in the bag on February 5.
Romney needs Florida and three big states to secure the nomination. Considering he has his home state locked, and that he's tied in New York with McCain, he'll have to win one more state, which could be Texas or Illinois, where he ties with McCain.
Of course, a Florida loss may be devastating for him.
Personally, I'm rooting for Romney. While I dislike most of his current platform, I have a feeling that-- if he won the election-- he wouldn't extend Bush's term by another four to eight years. He has a sensible health care plan (though the whole 'you'll get fined if you don't have insurance' thing isn't my cup of tea), and knows economics, whereas McCain's main issue is keeping troops in Iraq, with no emphasis on any economic concerns (he admitted he doesn't know economics very well; that may be a stupid statement, considering the likely chances that our economy will be hurting by the time he's sworn in). Plus, he has a record of being bipartisan, since both state houses in Massachusetts were controlled by Democrats during his tenure. McCain will have problems uniting the Republican party alone; imagine how uniting both parties would be.
Plus, Romney is currently the electoral college's least-ranking player. So he'll also put the Democrat in a good position from the get-go, at least in Virginia, Ohio, and Missouri, where he currently (as of mid-January) loses to all three Democrats by 10-20 points. Romney is the best candidate for the Democrats in both senses, whether he loses or wins.