Democratic presidential hopeful Bernie Sanders is encountering a fierce backlash for recent remarks about gender and race, facing charges that he's "tone deaf" in discussing Hillary Clinton's bid to become the first woman president and her efforts to woo African-American voters loyal to President Barack Obama.

The backstory: Rapper Killer Mike, who's stumped for Sanders around the country, ignited the firestorm during a campaign event at Atlanta's Morehouse College on Tuesday. Urging voters not to back Clinton simply because she's a woman, the entertainer related a conversation he'd recently had with a female voter.

"I talked to Jane Elliott a few weeks ago, and Jane said, 'Michael, a uterus doesn't qualify you to be president of the United States.' You have to be — you have to have policy that's reflective of social justice," Killer Mike said.

Read more: Clinton and Sanders Battle for Black Support as Campaign Shifts Focus to South Carolina

Though the rapper argued that the full context of his remarks made clear that he wasn't making a sexist jab at Clinton, his words struck a nerve — in large part because many critics believed they fit a larger pattern of Sanders' campaign dismissing the significance of sending the first woman to the Oval Office.

Asked during the Democratic debate in Milwaukee last week whether he worried he'd be "thwarting history" if he defeated Clinton, the Vermont senator sidestepped the issue of gender entirely.

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"Well, you know, I think, from a historical point of view, somebody with my background, somebody with my views, somebody who has spent his entire life taking on the big money interests, I think a Sanders victory would be of some historical accomplishment, as well," he responded.

Sanders opened himself to further criticism when NBC News asked him to weigh in on the controversy surrounding Killer Mike's remarks.

"What Mike said essentially is that ... people should not be voting for candidates based on their gender, but based on what they believe. I think that makes sense," he said on Thursday. "I don't go around, no one has ever heard me say, 'Hey guys, let's stand together, vote for a man.' I would never do that, never have."

The backlash was swift, with critics depicting those remarks as insensitive to matters of sexism and gender representation:

That's not all: Sanders found himself embattled on yet another front Thursday, after he told BET that Clinton has ferociously tied herself to President Barack Obama as part of a cynical ploy to win black voters.

"You know, Hillary Clinton now is trying to embrace the President as closely as she possibly can. Everything the President does is wonderful. She loves the President, he loves her and all that stuff," Sanders told the network. "And we know what that's about. That's trying to win support from the African-American community where the President is enormously popular."

Though Sanders has at times been a harsh Obama critic — even suggesting, in 2011, that the president deserved a left-wing primary challenger — Sanders went on to praise Obama himself, while acknowledging that they haven't always seen eye-to-eye.

"But you know what? I have enormous respect for the president. He's a friend," Sanders said. "We have worked together. I think he has done a great job in many respects. But you know what? Like any other human being, he is wrong on certain issues."

Clinton supporters seized on Sanders' remarks to argue that he was breaking his pledge to run a positive campaign — and suggested that Clinton would've been bombarded with criticism had she made similar comments.

Will it matter? Such controversies are, in part, the stuff of which modern elections are made. Whether they'll move votes is another question.

This much is clear: As Sanders looks to cut into Clinton's support with nonwhite voters and erode her advantage with women, his campaign would be far better off without the dual controversies.

While Sanders won women voters in New Hampshire and now trails Clinton by just three points nationally among women, according to the latest Fox News poll, further gains will be difficult if his campaign fuels the perception that he doesn't appreciate the significance many voters place on electing a female president, or if he appears dismissive of inflammatory remarks from supporters and surrogates.

As Sanders gains on Clinton nationally — and may score yet another early state victory in Saturday's Nevada caucuses — scrutiny of how he handles such matters will only heighten.