Well, if it's a three-way horse race to the White House, it's looking pretty grim for the Republicans:
http://polltracker.talkingpointsmemo.com/contest/us-favorability-obama?ref=fpblg
http://polltracker.talkingpointsmemo.com/contest/us-favorability-romney?ref=fpblg
http://polltracker.talkingpointsmemo.com/contest/us-favorability-gingrich?ref=fpblg
Obama's favorability ratings have dipped no lower than 45% his entire presidency, and hover around 49%.
Lousy for a sitting president, but not bad relative to his competition: Gingrich's rating is at 26% and falling. Romney's is at 38%.
I suppose a lot of the negativity can be ascribed to the brutal primary season. It's not news when a Republican thrashes Obama. They've been doing that for about 4 years now (counting the 2008 election cycle). It is news when Romney bashes Gingrich and vice versa.
The thing is that Gingrich seems to alienate people the more they get to know him.
David Frum points out: "It's striking that almost none of Gingrich's former colleagues in the House has endorsed him for president. Striking that nobody associated with a past Republican presidential association has done so."
Romney's problem is that no matter how much money he spends, he's got classic Gore/Kerry-itis. You can see he's done some impressive things, but you can't help but just kind of not relate to him as a human being. He's kind of plastic. He says off-handedly that he made a "small" amount of money in speaking fees last year, which turned out to be $375k. To most Americans, that ain't small. He jokes about betting $10k as if it were $5. He pays a little over 15% in federal taxes. (Dubya was rich too, but he sure didn't seem it.) Then there's the weird do-on-the-roof family vacation story. And (alas, I don't think it matters but it does to many) he's Mormon. His wealthy lifestyle, his religion, and his personality all seem kind of "foreign" to a lot of Americans, in a more visceral way than "Obama is a Kenyan Socialist Muslim!" ever did.
You add it all up and I really don't see Obama losing this thing. Maybe if he were Bill Clinton he could screw it up with some bizarre indiscretion, but this is No Drama Obama we're talking here.