Alabama Rep. Parker Griffith is leaping off Obama’s coattails. The freshman Democrat from Alabama was to announce on Tuesday that he is switching parties to join the GOP. A radiation oncologist, Griffith says the health-care bill is the main reason he’s switching parties. Griffith will be the first Republican to ever hold the historically Democratic district. Rightwing blogger Erick Erickson, meanwhile, is already calling for Republicans to challenge Griffith in a primary and cites an old GOP attack ad accusing him of under-treating cancer patients in order to make more money.