I'm 67 years old and have followed presidential elections since 1960.  I have never seen it to be an issue with any white man.  I find that to be racist. 
"Ballot access rules vary by state, but in general, you don't have to prove eligibility unless someone challenges it. Article II of the U.S. Constitution requires that a presidential candidate be a "natural born citizen"—in other words, a citizen born in this country or, according to traditional interpretation, born to U.S. citizens overseas (as opposed to a naturalized citizen born overseas).
Instead, they take the major parties' word for it. In presidential primary elections, most states put "generally recognized candidates" on the ballot automatically." Slate Magazine
Even if Barack Obama was born overseas, he still would have been eligible because of his mother's U.S. citizenship.