The short answer to the question posed above is: Maybe so, maybe not. A person who is a racist may oppose President Obama, just as a person who is not a racist may not care for him or his policies; approval of or opposition to Mr. Obama or his policies may either be all about his race, or it may have absolutely nothing to do with his race. I don't believe that all opposition to President Obama and his policies is because of the color of his skin. In fact, I don't consider President Obama to be "a black President"; I regard him as my President, who just happens to be (half-) black. But I also realize that he comes from the left wing of the Democratic Party, and his views just may be to the left of those of most Americans; so, I tend to see much of the opposition to the President as being more a matter of ideology than race.
I said, "much," not "all" or even "most." There definitely is more than a mere hint of racism in some of the opposition to the President and his policies; that's blindingly clear. To some, there's absolutely NOTHING that the "(White) House Ni**ah" could say that would be acceptable, simply because he is that: A Black Wannabe-President in the White House (they definitely don't see him as their President).
BUT (and here's where I'm going to be castigated and called everything but a Child of God by many of my fellow blacks and liberals): I see little or no difference between someone SUPPORTING him for no reason other than his race, and someone OPPOSING him for that reason alone. To me, those are both racist attitudes.
Let me pause here and admit to a bit of race-consciousness (okay, racism) and maybe more than a hint of inconsistency and probably some hypocrisy on my part when it comes to the President: When, in 2008, the top possible contenders for the Democratic nomination were Hillary Clinton and Barack Obama, I considered both candidates, and scoured their backgrounds and positions as carefully as I was able to. Their positions seemed to be so close on issues that mattered to me (except, maybe, for the Attack on Iraq thing) that I could have supported either with equal enthusiasm and comfort. So, I went with Sen. Obama --- for racial reasons, primarily. Please don't tell me that was not a valid reason to support or oppose anyone; I KNOW that. But I did, anyway.
I'll admit, too, that had Gen. Colin Powell been the Republican nominee, I probably would have voted Republican instead of Democratic --- depending, of course, on who his running mate was. But my support for the Good General would have been because of his positions on issues, not because of his race; he comes across to me as being cut from the same cloth as such old-time Republicans as Abraham Lincoln, Ed Brooke, Nelson Rockefeller, Chuck Percy, and even George Romney --- none of whom was a theocrat, as are virtually all of the leaders of the modern GOP.
While I'm on that subject, let me say: If the Republican Party had had the smarts that God gave a billy goat, and the foresight to have nominated Condoleeza Rice in 2008, I truly believe that we would now, in 2015, be halfway through a second Republican administration, instead of a liberal Democratic one. Seems ridiculous? Consider: Dr. Rice is black and female, both of which seem to carry a lot of weight these days; she was (and, presumably is) more conservative than George W. Bush, who comes from what is actually a rather moderate Republican household; she was definitely more hawkish than he was; she's probably more intellectually gifted; and, as the daughter of a southern Presbyterian minister, she wouldn't have automatically alienated the evangelicals, as did the ex-Episcopalian "W" and, later, the Mormon Mitt Romney. The only possible opposition from Republicans would have been from the extreme racist fringe, but even people over there would have had to hold their noses and support her, because the alternative would have been (what seemed to them to be) an extreme leftist guy who was equally (gasp!) black.
But they were stupid, and didn't nominate her (of course, I wouldn't have supported her just because her ass was as black as mine, but many blacks would have). So here we are now (thank, God, I say!) well into the second of two relatively liberal Democratic administrations --- and, I fervently hope, getting ready to launch a third! I happen to believe that the Republicans will nominate Mr. Bush, the most-electable of their candidates next year, and I also believe that his running mate will be the very conservative black female, Mia Love --- and I still won't support that ticket, no matter how black she is; not with either Hillary Clinton or Bernie Sanders heading the Democratic ticket. The GOP will have a dilemma, though; while Mrs. Love will swing many of the very powerful, usually politically and socially conservative black televangelists to their side, many others won't be able to get past the fact that she's not an evangelical or fundamentalist Protestant --- she's a (gasp! horrors!) Mormon!
Actually, at this point in time, I believe that if the GOP had a Trump/Carson ticket, they'd win. I can only hope that the country will come to its senses before November, 2016, and that Donald Trump and Dr. Ben Carson will only enter the White House at the invitation to the Democrat residing there!
Don't let me get too carried away. Just let me say this, as this is what I believe: No, not all opposition to President Obama is because of his race. Not all support of him is because of his race. The fact, alone, that one supports or opposes President Obama does not mean that one is, or is not, a racist. I think that a helpful exercise would be to ask yourself three questions: (1) What are the three main reasons I oppose (or support) Barack Obama as President; (2) would I still oppose (or support) him if his position on each of those things was the opposite; and (3) if President Obama's positions were exactly the opposite of his stated positions on those issues are now, and Sarah Palin's positions were exactly as his are now, would I support her? If you can answer those questions candidly and with no reference to race, maybe you're not a racist; if you can't, you probably are.