I don't understand what it is to play the race card, so I don't use that expression. Race is fine to bring in when it's relevant and not ok to bring in when it's not, but such an expression seems to me to assume that it's always inappropriate. But I did want to say something about the following remarks (taken from here):
Nobody really thinks that Bush or McCain have [sic] a real answer for the challenges we face. So what they're going to try to do is make you scared of me. You know, he's not patriotic enough. He's got a funny name. You know, he doesn't look like all those other presidents on those dollar bills, you know. He's risky.
Notice that there's no explicit mention of race here. He also doesn't reference his middle name 'Hussein'. He just refers to it obliquely (or perhaps he's referring to his whole name, but it's his middle name that people have used against him). He also makes a veiled reference to his dark complexion with the comment about presidents on dollar bills. But he doesn't use any race terms. Further, when McCain called him out for playing the race card, his campaign denied that the dollar bill reference had anything to do with race. It was about his not being a Washington insider. (I sure hope he continues this line of defense, because if it becomes clear that he sees the founders of this country as evil Washington insiders whose government we need to do away with, then he's not going to be getting very far.) It seems as if he's dancing around the issues he wants to get across without saying anything about them. It makes it sound as if he's trying to engage in the politics of racial fear without losing his appearance of being a post-racial candidate of hope.
Compare his very similar speech from June 20:
The choice is clear. Most of all we can choose between hope and fear. It is going to be very difficult for Republicans to run on their stewardship of the economy or their outstanding foreign policy. We know what kind of campaign they're going to run. They're going to try to make you afraid. They're going to try to make you afraid of me. 'He's young and inexperienced and he's got a funny name. And did I mention he's black?'
Then the previous day (from the same source):
They're going to try to make me into a scary guy. They're even trying to make Michelle into a scary person. Right? I don't know, before I wasn't black enough. 'Now he might be too black. We don't know whether he's going to socialize - well, who knows what.'