Fair points, but the Republican primary electorate is way different from the Democrat primary electorate that nominated Clinton and Biden. As for McCain and Romney, 2008 McCain’s biggest rivals were Mike Huckabee, who was way too committed to evangelicism to work on a national level, Ron Paul, who was never going to win, and Mitt Romney (lol), and in 2012 Romney’s biggest rivals were Santorum (see Huckabee), Ron Paul (see Ron Paul), and Newt Gingrich, who was past his expiration date.