"Most of them could care less about the man."
If they could care less, that means that they care some. I think you meant to say they couldn't care less.
"I understand there's sort of a holy aura around the president, where he's viewed as some sort of quasi-deity because he's not George W. Bush"
Nobody claims these things except people who don't like him.
"People that are watching Mythbusters are already interested in science and that sort of thing, why is bringing politics into the show going to influence people to like science?"
The whole point is to get people to watch Mythbusters who don't normally watch the show. Then they might see that science doesn't have to be boring and develop an interest in it.