I might agree...except "Republicans" aren't going to be trying to beat President Obama in 2012. It's going to be a specific Republican running against him, and that's what looks to be a problem for the Republicans at the moment. Because there isn't really a Republican right now who is going to run who could beat Obama. In fact, each potential Republican candidate seems to be worse than the last.
2012 might not be a repeat of 2008, but it's looking like another 2004 to me, except with the positions reversed. In 2004, President Bush was wildly unpopular, and the campaign of "anybody but Bush" was going strong. Except when we got around to the actual election, it turned out that "anybody" was John Kerry, and for the majority of voters, "anybody but Bush" worked a lot better than "Kerry instead of Bush".
There's no question that right now Obama looks like he's beatable in 2012. But while his unpopularity might be going up, that doesn't mean the voters will prefer ANYONE to Obama. And the problem for the Republicans is that they seem to be holding a contest to find the biggest jackasses they possibly can, apparently in the belief that literally anyone can beat Obama. I'm not so sure.