President Barack Obama acknowledged in unaired portions of a "60 Minutes" interview that his campaign ads sometimes go "overboard" when it comes to attacking Mitt Romney. But "that happens in politics" and voters deserve to see the "sharp contrast" between the candidates, the president said.

"I'm making a positive case for a specific plan for how we move the country forward," Obama told the venerable news program in a snippet available on its website.

"Do we see sometimes, us going overboard in our campaign, the mistakes that are made or the, you know, areas where there's no doubt that somebody could dispute how we are presenting things? That happens in politics," the president said. "There is a sharp contrast there. But the stakes are high." "The truth of the matter is most of the time we're having a vigorous debate about a vision for the country," he said. "Is it going to be sharp sometimes? Absolutely."

Obama's remarks drew a swift rebuke from the Romney campaign, with spokesman Ryan Williams saying the incumbent and his allies "have repeatedly shown a reckless disregard for the truth—all while claiming to be concerned with 'the facts.'"

"The real test now is whether or not the president will change course and honor his long-discarded promise to change the tone in Washington," Williams said.

Obama campaign spokesman Adam Fetcher responded that Romney should not "shed crocodile tears over a legitimate discussion of his record and policies."

"While issues can sometimes get obscured in the context of a political debate, the facts do matter to us—unlike the Romney campaign, which bragged that it wouldn't be dictated by fact-checkers," Fetcher said. "We constantly strive to get things right and tweak them if necessary.

"If he's so offended by his own positions, maybe he shouldn't have taken them in the first place," Fetcher said.