The 2012 Election is going to be easy for us all to follow. It will be Obama running on the Democratic ticket with a TBD Republican. Frankly, it is not going to matter who the Republican candidate is if Obama's approval ratings remain in the 60% range.
The election is a while away and Obama's approval rating may drop by then but one major point looms. In order to run for President, you would pretty much have to announce your intentions of running 2 years prior to the election. This means that in 18-24 months, you would have to declare your intentions to run to be able to raise enough money for a serious campaign.
If Obama's approval ratings remain high for that amount of time, what legitimate Republican candidate is going to run against him? Not many.
That would likely set the stage for a few candidates who have run in the past and would likely not run again in 2016. Those candidates would be Mitt Romney and Mike Huckabee. Sarah Palin is an interesting candidate to follow because she could set herself up for a run in 2016 and run on more experience but all of her popularity may be gone by that point.
She was not too popular among the voters and she looked like a fool at times in interviews but her popularity among the Conservative base will be at its peak in the 2012 election. She may become more credible to independents and cross-over voters in 2016 but it could be at the expense of losing popularity among the base.
If Obama's approval ratings remain high, Bobby Jindal would likely just wait. The Republicans appear content with Huckabee and Romney as options anyways, so let the 2012 bout go on.