It covers alot of ground for them in a short time. It's much easier to dismiss their opponents as racists than explain why Obama has repeatedly lied to them (his supporters) about practically everything.
There we go again into the irrational. Obama of course has not lied about practically everything. Now why would we be so eager to make such irrational statements?
Those who question such "lies" are concerned about policy not birther concerns and his personal legitimacy. I don't see any reason why a person who critisizes Obama on his backtracking on policy would be racist but the birthers and those pushing for personal illegitimacy are another story.