The increasing likelihood that Vice President Harris, the White House’s chief defender of abortion rights, will emerge at the top of the Democratic ticket has buoyed party leaders counting on abortion to invigorate voters in November.

While President Biden has long struggled to talk about abortion — often declining to say the word and fumbling his answer to a question on abortion during his debate against Donald Trump — Harris has spoken forcefully on the issue to draw contrasts with Republicans. She embarked on a “reproductive freedoms tour” of key battleground states this year to decry abortion bans and has hosted frequent meetings with Democratic state legislators, attorneys general, abortion providers and advocatesto strategize on how to fight the bans.

“There is no question that having her at the top of the ticket helps really elevate this issue,” said Celinda Lake, a Democratic pollster who worked on Biden’s campaign in 2020 and is part of the 2024 Biden polling team. “She was our strongest voice on it anyway. It galvanizes women voters around this issue, it galvanizes a whole generation of younger voters around this issue and people of color.”

Abortion rights advocates say they hopehavingone of their fiercest allies as the Democratic nominee in the first presidential contest since the Supreme Court eliminated the constitutional right to abortion in 2022 could not only help the party defeat Trump, but maintain control of the Senate and recapture the House.

On Sunday, within hours of Biden dropping his reelection bid and throwing his support behind Harris, she drew endorsements from two prominent abortion rights groups. Mini Timmaraju, president and chief executive of Reproductive Freedom for All, moved up her organization’s board meeting to quickly back Harris as the Democratic nominee.Emily’s List, a political action committee that supports Democratic women who champion abortion rights, also endorsed Harris. Planned Parenthood’s leader, Alexis McGill Johnson, praised her for being the first vice president to visit one of their clinics while in office.

Harris “didn’t need to go through an evolution on the issue. She’s been there from the beginning,” Timmaraju said. “She’s the kind of candidate who’s going to generate more enthusiasm from elements of our movement … including independents and Republicans who are really unhappy post-Dobbs.”

By contrast, Biden, a devout Catholic whose position on abortion has shifted during his lengthy political career,has at times during his presidency spoken about abortion in euphemisms — lamenting in reelection campaign stump speeches about Republicans wanting to take away “freedoms,” including reproductive rights.

Biden was widely criticized by Democrats for not immediately and forcefully blasting the Supreme Court abortion decision. But he took modest steps to try to protect abortion access through federal agencies. And he repeatedly said he would sign legislation codifying Roe v. Wade if Congress passed such a law.

Biden aidessay they had believed abortion would bring young voters, liberals and people of color — Democratic constituents whose support for the president has been softening over recent months — back into the fold, but Biden largely deferred to Harris to serve as the primary messenger on the issue.

Harris long struggled to find her footing as vice president, initially tasked with immigration as the number of migrants surged. But with the fall of Roe, Harris found an issue key to the administration’s success that she could forcefully lead on.

“In the case of the stealing of reproductive freedom from the women of America, Donald Trump is guilty,” Harris said at a June event at the University of Maryland marking the second anniversary of the overturning of Roe. “And over the past two years, we have seen the impact of these Trump abortion bans — the horrific, heartbreaking reality that women have been facing every single day in our country.”

About one-quarter of all Americans said access to abortion is “one of the single most important issues” to their vote for president, according to a Washington Post-ABC News-Ipsos poll conducted this month.Among Democrats, 45 percent said abortion is a top issue.

Abortion rights advocates in nearly a dozen states are pushing for ballot measures to explicitly protect abortion access. With few tools to circumvent state bans, the abortion rights movement is appealing directly to voters as a key strategy. Voters have consistently sided with abortion access since Roe was overturned, including in red states such as Ohio, Kansas and Kentucky. Democrats outperformed in the 2022 midterms in large part because of voter backlash to sweeping abortion bans in Republican-ledstates like Texas and much of the South.

Harris, who appears to have an inside track to securing the nomination, also received high-profile endorsements from Democratic governors and lawmakers on Capitol Hill who have strongly advocated for abortion rights, including Govs. Gretchen Whitmer (Mich.) and Josh Shapiro (Pa.); former House speaker Nancy Pelosi (Calif.); and Sens. Patty Murray (Wash.) and Tina Smith (Minn.).

“There’s a real electric energy right now in the party,” said Jessica Mackler, the president of Emily’s List. “Just looking at the outpouring of support that we’ve seen in the last 24 hours — really even less than 24 hours — for the vice president, people are fired up and they are excited about her. And a lot of that is about the leadership that she provides on reproductive rights.”

Harris, a former district attorney who once specialized in prosecuting child sexual assault cases, has a long history of standing up for abortion rights. As California’s attorney general, her department fought antiabortion advocates who recorded undercover videos of Planned Parenthood. As a U.S. senator, she grilled then-Supreme Court nominee Brett M. Kavanaugh on abortion, asking whether he could “think of any laws that give the government the power to make decisions about the male body.”

After some back-and-forth, Kavanaugh responded: “I’m not thinking of any right now, senator.”

Antiabortion groupshave rushed to issue statements painting Harris asan extremist.

“Harris is so committed to abortion that she can’t see anything else — including the developmental stages of children before birth or the real needs of women,” said Marjorie Dannenfelser, president of SBA Pro-Life America, a leading antiabortion group that is planning to spend $92 million this election cycle.

She added, “While Joe Biden has trouble saying the word abortion, Kamala Harris shouts it.”

The Harris campaigndeclined to comment.

Harris made history as the first woman — and woman of color — to serve as vice president. That, coupled with her track record of fighting for abortion access, makes her uniquely qualified to bring the issue to the forefront of voters’minds, her allies say.

“She can, better than anyone, prosecute the case against Donald Trump and why he would be so damaging for our future,” saidMurray, the first woman to serve as the president pro tempore of the Senate.

Earlier this month, delegates at the Republican National Convention approved a party platform that abandoned the GOP’s long-standing support for national abortion restrictions in favor of Trump’s leave-it-to-the-states approach. Trump has frustrated antiabortion leaders by not endorsing federal restrictions after some pushed him to support a nationwide ban onabortion after 15 weeks.

Biden officials have said the federal government’s ability to intervene in state legislation is limited, even as his administration issued guidelines, executive orders and legal interpretations aimed at protecting abortion access.

If Harris secures the nomination, several abortion rightsadvocates said they would urge her togo further than Biden and release her own agenda outlining specific policies to protect abortion.

Harris was extraordinarily careful not to make moves to prepare for a presidential bid before Biden announced his decision, and her team is still working through her policy positions, according to a person familiar with internal planning. It is not yet clear how she might lay out her own policies on abortion and whether she will be willing to diverge from the president.

“Harris is part of an administration that had carefully crafted policies based upon what the president thought was best and what he thought was achievable,” said Pamela Merritt, the executive director of Medical Students for Choice. “This is an opportunity, should she get the nomination.”

Emily Guskin contributed to this report.