They're kidding, right? The goal may be to associate Obama with Bush in the eyes of the public (unlikely to stick) or just to make him seem like a pandering flip-flopper (more likely) but it won't work when the conservative candidate is accurately described as a third Bush term. Do I even need to point out how wrong these arguments are? Yes, Obama supported the imperfect FISA bill, but whatever you think of that decision, the new legislation is still more than the Bush administration wanted and better than the alternative bill already passed in the Senate, as Mort Halperin argues here. Every other argument these conservatives are making -- that Obama is going to change his position on Iraq (he hasn't), that he is wildly pro-gun (ask the NRA what they think), etc. -- is laughable.
It may be a side effect of Obama's ability to communicate well with conservatives, but it also seems like they want to jump on the Obama bandwagon, the same way they will try to reclaim historical figures like Martin Luther King, Jr.