I am curious about that statement too. Maybe the argument was something like "Black man is running for President." That fact alone was enough to cause racial tensions.
I would add to that his infamous “god and guns” speech, and his behavior in the primaries, including his shameful dance around the Jeremiah Wright issue.
You and some other commenters in the replies are making this claim. So yeah, Obama was black, and some people were excited to vote for him because he was black. That's not what I'm asking.
Did his Facebook ads specifically take advantage of the fact that he was black? Did his ad campaign benefit from inflaming racial divisions?
To be fair, advertising from the trump campaign may not have played on racial tensions either. The thing people are upset about is the russian interference. The russians bought ads and made posts that clearly stoked tensions, and Facebook was negligent in preventing this.
Blacks were 19% more likely to vote for Obama because he was black and 2% less likely. Whites were 5% more likely to vote for Obama because he was black and 6% less likely.