The New York Times on Sunday, in a story titled “Democrats in Split-Screen: The Base Wants It All. The Party Wants to Win,” described a “growing tension between the party’s ascendant militant wing and Democrats competing in conservative-leaning terrain.” The reporters, Alexander Burns and Jonathan Martin, cited Senator Bernie Sanders as a leader of the former group and Georgia congressional candidate Jon Ossoff as representative of the latter. At one point, the piece referenced “tension between Mr. Ossoff’s message and the appetites of the national Democratic base.”

Hours after the Times article was published, FiveThirtyEight statistician Nate Silver took issue with such framing, igniting a Twitter debate over who, exactly, comprises the Democratic “base.” This may seem like a matter of semantics to some, but to others it’s a loaded term whose definition has real implications for the future of the Democratic Party—not just in courting new voters, but in not taking for granted its longtime supporters.

The Times was hardly the first publication to substitute Sanders supporters for Democratic base voters. In an article about Senate Democrats last month, the Huffington Post made reference to “their restless progressive base, which would like to see the party embrace Sanders-style economic populism.” But as National Journal politics editor Josh Kraushaar‏ observed on Sunday, Hillary Clinton actually tied Sanders in last year’s primary among voters who called themselves “very liberal.” (She won “somewhat liberal” and “moderate” voters by big margins.)

That Wall Street Journal analysis of the 2016 Democratic primary is strong evidence against the claim that Sanders, who isn’t even a registered Democrat, represents the party base. As the Journal noted, “Sanders won big margins among independents who cast ballots in Democratic contests. But he lost Democratic Party members by close to 30 percentage points.”

“If you’re talking about the Democratic Party base, it’s actually kind of more of a Clinton base,” Silver said on a FiveThirtyEight podcast on Monday. “If you’re talking about liberal activists or progressive activists, it’s a slightly different connotation.”

“I think there’s a lot of reporting that wants to kind of play up the conflict between the Bernie wing of the party and the establishment, which kind of leaves out the fact that Hillary Clinton had a lot of support from people who are kind of classically part of the Democratic base, including African-Americans, women, Hispanics, older Baby Boomers,” Silver said. “I mean, these are very, very major parts of the Democratic coalition.” He acknowledged “fairly clear evidence that the Democratic Party as a whole is moving to the left, and the influence of Bernie Sanders and politicians like him is an important reason for that,” but said “the notion that anyone who pushes back against that is the establishment and not part of the grassroots is wrong.”

“I think in most areas of the country, the base of the Democratic Party is moderates,” said Jim Kessler, co-founder of the centrist Democratic think tank Third Way. “I’ve always felt that the Democratic Party has to row with two oars with equal fervor. We can’t win with just liberals.” Earlier this year, he cited exit poll data showing most Democratic voters identify as “moderate” or “conservative.” “I think it would be a dangerous experiment to say the party could move much further left and appeal to as broad a group of people,” Kessler told me.

The debate over who comprises the Democratic base isn’t just about defining the party’s identity, both ideologically and demographically, but about whether certain Democratic voters get enough recognition for their loyalty in the voting booth. No group of voters is more dependably Democratic than black women, who voted overwhelmingly for Clinton over Sanders, by a three-to-one margin, even as he narrowly won younger black voters. In the general election, black women “were by far Clinton’s strongest supporters, at 94 percent,” according to The Washington Post.

“I think the most reliable Democratic voters out there are older black women,” Democratic pollster Celinda Lake told me. While the Bernie coalition doesn’t vote Republican, some them do flirt with third parties, while the older black women don’t.” Lake said her description of the Democratic base would include self-described liberals, unmarried women under 55, and people of color in general, but she stressed, “The strongest part of our base is older African-American women.

And yet, dozens of prominent black women in politics recently sent a scathing letter to Tom Perez, the chair of the Democratic National Committee, saying the party hasn’t reciprocated their commitment to it, and that they will no longer be “silent partners.” “The Democratic Party has a real problem. The data reveals that Black women voters are the very foundation to a winning coalition, yet most Black voters feel like the Democrats take them for granted,” they wrote. “The Party’s foundation has a growing crack and if it is not addressed quickly, the Party will fall even further behind and ultimately fail in its quest to strengthen its political prospects.” The signatories, which included several state senators and representatives, called on the DNC to meet with black women leaders. Perez promised to do so, telling the Post in a statement, “While black women are at the core of our party and of the resistance, they are too often taken for granted. We must change this.”

“I think a really important lesson we must learn from the last election is that women of color are our base of support—our tried and tested Democratic supporters,” said Shannon Watts, the founder of Moms Demand Action for Gun Sense who is mulling a Democratic bid for Congress in Colorado. “They are influential voters. They should be influential within the party.”

Citing the Perez-Sanders “unity tour,” Watts says the Democratic Party’s post-election leadership has been lacking in gender diversity. “It doesn’t feel very unifying when the stars are mostly male,” she told me. “I would like to hear a whole lot more from Kamala Harris and Maxine Waters and Pramila Jayapal.”

One prominent black woman in the Democratic Party isn’t as concerned. Donna Brazile, the former DNC chair, said it’s “not my view” that Sanders and his supporters are inappropriately used as shorthand for “the Democratic base,” to the exclusion of groups like black women. “Base is as broad and diverse as the party itself,” Brazile told me in an email. “From millennials to non white voters, Democrats have an opportunity to expand and attract the kind for voters needed to win at the grassroots level. The most important challenge facing the party is its ability to recruit candidates that will inspire a new generation of voters to register and get out to vote.”

In other words, the big tent must get even bigger. The challenge for party officials is to make everyone underneath it feel welcome.