Despite some tensions with his fellow Republicans, Chris Christie is well-positioned to become the front-runner for the GOP presidential nomination in 2016. He's poised to easily win another term as governor; he polls strongly against Hillary Clinton; and he's successfully tapped into voter discontent about the partisanship, political posturing, and general bullshittery that plagues Washington. There's just one problem: Christie is very overweight — so much so that one esteemed former White House physician (a Republican, in fact) is worried he could die in office....