UPDATE: President Barack Obama responded to Sununu's comments in an interview with radio host Michael Smerconish. Here's what he had to say, according to Politico:

"I don't think that there are many people in America who would question General Powell's credibility, his patriotism, his willingness to tell it straight.

"So any suggestion that General Powell would make such a profound statement in such an in such an important election based on anything than what he thought was going to be best for american, I think, doesn't make much sense."

ORIGINAL: Former New Hampshire Gov. John Sununu, a Romney campaign co-chair and top surrogate, suggested Thursday night during an interview with CNN's Piers Morgan that former Secretary of State Colin Powell endorsed President Barack Obama because both are African-American.

Here's the transcript of the interview:

MORGAN: "Colin Powell has decided to opt for President Obama again, despite apparently still being a Republican. Is it time he left the party?"

SUNUNU: "Well, I'm not sure how important that is. I do like the fact that Colin Powell's boss, George Herbert Walker Bush, has endorsed Mitt Romney all along. And frankly, when you take a look at Colin Powell, you have to wonder if that's an endorsement based on issues, or whether he's got a slightly different reason for preferring President Obama."

MORGAN: "What reason would that be?"

SUNUNU: "Well, I think when you have somebody of your own race that you're proud of being President of the United States, I applaud Colin for standing with him."

Over at The Atlantic, David Graham breaks down the explanation Powell detailed on Thursday: He has never been thrilled with Romney's foreign-policy stances.

Watch the clip of Sununu below: