Why Donald Trump trips over Obama's heritage

Washington (CNN)Donald Trump declined to use his Sunday show opportunities to clarify his thoughts on President Barack Obama's birthplace and repeatedly avoided direct answers on the subject. One explanation: Those at the base of his support are the same who question the president's legitimacy -- and playing to that fringe has been Trump's ticket to success so far. He stoked those inaccurate beliefs on NBC's "Meet the Press," when he was asked whether he'd be comfortable with a Muslim president. "Some people have said it already happened, frankly," Trump responded in a clear reference to Obama. "But of course you won't agree with that." "I don't talk about people's faith. Now, in all...