The media will now portray it to be so in the General Election, you will see articles in Newsweek and Time with Barack in some angelic pose and "BARACK OBAMA AND RACE: IS AMERICA READY?" Liberal pundits, on their cable and print mouthpieces will hammer it home. McCain will have trouble overcoming this, people will vote for Obama like this in no specific order: He is the same race as them, they want to seem hip and progressive, they are white and don't want to seem like racists...you get the point. This race is based on race. Lets not all be naive.
What's to overcome?
There are more Whites than anything else in America, period. McCain doesn't have to overcome anything. He just has to keep his mouth shut, keep distancing himself from Bush, and waltz to victory in November.
What you will see is polls saying that Obama is leading in areas that he will eventually lose by double digits. Why? Because white people lie to pollsters for the reasons you outlined...not wanting to be seen as racist
solely because they are registered Democrats who have no plans to vote for Obama in November.
Yes, there are Blacks supporting Obama because he is black. But there are also Blacks - just as there are Whites - supporting him because he is NOT a Clinton (or a Bush).
I supported him in the primaries, because I could not live with the possibility of Hillary becoming President. But when November comes, I will vote my conscience and my wallet and as his platform stands right now, I do not feel he has the best interests of my wallet in mind.