Those advances have played a role in her surging overall numbers, which have seen Warren expand her lead over the African-American candidates in the primary — Sens. Kamala Harris and Cory Booker — and even overtake Joe Biden and Sen. Bernie Sanders in some state and national polls.

“It’s certainly a dramatic shift that had to be noticed by the Biden campaign — and also Sanders, Harris and Buttigieg,” said Tim Malloy, Qunnipiac’s polling analyst. “Other [candidates] aren’t moving. And if they are, it’s in the wrong direction.”

Biden has long commanded an outsized portion of black voters, many of whom look favorably upon his service as vice president to President Barack Obama. In both the Quinnipiac and Morning Consult polls. Biden holds 40% of their support.

Warren, however, has faced doubts about her appeal to the party’s most loyal constituency. But months of outreach and targeted policy proposals appear to have made a mark.

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“Elizabeth Warren has been speaking directly to a lot of black women’s issues,” said Avis Jones-DeWeever, a lead researcher on last month’s Essence-Black Women’s Roundtable poll, which has Warren in third place behind Biden and Harris. “I’m seeing those direct specifics that [she’s] looking at and focusing on.”

Her April appearance at the She The People forum — the first-ever presidential candidate forum focused on women of color — marked a significant milestone for her campaign, particularly in regards to black women. Following her remarks to a majority-black female audience, the Warren campaign sharpened its messaging to include issues unique to black Americans like maternal mortality rates and racial justice, an approach that some activists say helped alter the perception that Warren was a detached policy wonk.

“In terms of her building trust and authenticity, I believe that was the moment,” said Aimee Allison, founder and CEO of She The People. “The thing about [black women] is that we have networks of networks. When she impressed a room of 2,000 women of color, I could just see months later that she started getting people’s attention.”

Since then, Warren has continued to hold listening sessions with black women’s groups and community activists. Ahead of July’s Netroots Nation conference, one of the largest gatherings of progressive activists, Warren held a roundtable with a group of black organizers who then took to social media to express support for her platform.

“Warren is attempting to rewrite the playbook as it relates to what it takes to win the nomination,” said Antjuan Seawright, a Democratic strategist based in South Carolina. “But I don’t know how anyone can secure the nomination without overwhelming black support across the board.”

Patrick Murray, director of the Monmouth University Polling Institute, pointed to the broadening of Warren’s base — from white college-educated Northeastern elites to working class people and women of color — as one of the most significant developments in the race at this point. A majority of Warren’s black supporters are women, who are the most politically active of the bloc.

Murray and other pollsters maintain that Warren’s gains with African-Americans are likely more reflective of Warren’s growing popularity overall, and not necessarily a trend that is unique to black voters.

The Massachusetts senator is also seeing a rise in support among college-educated white women, going from 25% in the August Quinnipiac poll to 37% in September.

“More people are becoming comfortable with her as one of the alternatives [to Biden],” Murray said, also noting that views of her among moderates and conservatives should carry just as much weight as other groups. “She has a message that she’s a good fighter, regardless of where you are in this race.”

Still, Warren has some distance to go with black voters to threaten Biden’s hold. In South Carolina — the early nominating state where more than 60% of the primary voters are African-American — a Winthrop University poll released Tuesday gave the former vice president a 46%-9% lead over Warren among black voters.

She’ll need to do considerably better there and in a handful of other Southern states where black voters will cast a majority of the primary vote on Super Tuesday.

Recent polls suggest Warren is moving in the right direction. In a July FOX News poll in South Carolina, the Massachusetts senator captured 2% of the black vote. In the Winthrop poll roughly two months later, she was at 10%.

“If you’re African-American, Warren may not have been someone you knew very well,” Murray said. “You knew Joe Biden, sure, but now you’re paying more attention.”