Minutes after the Supreme Court voted to overturn Roe v. Wade last summer, a group of West Wing aides raced to the Oval Office to brief President Biden on the decision. As they drafted a speech, Mr. Biden was the first person in the room to say what has been his administration’s rallying cry ever since.

“He said at that time, ‘The only thing that will actually restore the rights that were just taken away are to pass federal legislation,’” Jen Klein, the director of the White House Gender Policy Council, recalled in an interview.

But if the prospect of codifying Roe’s protections in Congress seemed like a long shot a year ago, it is all but impossible to imagine now, with an ascendant far-right bloc in the House and a slim Democratic majority in the Senate.

Instead, with the battle over abortion rights turning squarely to individual states, officials in the Biden administration are working with a limited set of tools, including executive orders and the galvanizing power of the presidency, to argue that Republicans running in next year’s elections would impose even further restrictions on abortion.

“Make no mistake, this election is about freedom on the ballot,” Mr. Biden said Friday at a Democratic National Committee event, where he collected the endorsements of several abortion-rights groups.

On Saturday, Vice President Kamala Harris will deliver a speech in North Carolina marking the one-year anniversary of the Supreme Court’s decision to eliminate the constitutional right to an abortion after almost 50 years.

Ms. Klein, who recalled refreshing news websites on the day the decision came down last June, said that she was “shocked but not surprised” by the court’s ruling in Dobbs v. Jackson.

She added that “efforts to really take extreme action do not represent the majority of opinion of where people are on this.”

The White House has argued that Mr. Biden is reaching the legal limits of his powers through executive actions. On Friday, his latest executive action in response to the Dobbs decision ordered federal agencies to look for ways to ensure and expand access to birth control.

Mr. Biden previously has issued a memorandum to protect access to abortion medication at pharmacies and taken action to protect patients who cross state lines to seek care. The Justice Department has taken legal action against some states restricting abortion. And the Food and Drug Administration’s approval of the abortion-pill drug mifepristone was quickly challenged in the courts. (In April, the Supreme Court issued an order to preserve access to the pill while justices reviewed the case law.)

As the White House has clarified its message around abortion rights, framing the fight as one in support of privacy, safety and civil rights, so has the president. Mr. Biden, a Catholic who attends mass almost every week, has struggled throughout his career with defending abortion rights. Since Roe was overturned, he has grown more outspoken.

“I think that he is somebody who really has his own personal views, and has also been quite clear that Roe v. Wade was rightly decided,” Ms. Klein said.

Recent polling shows that a majority of Americans may feel similarly. A USA Today/Suffolk University poll conducted this week found that one in four Americans said that restrictive abortion bans enacted at the state level have made them more supportive of abortion rights. Another poll, conducted by PBS NewsHour, NPR and Marist, said that 61 percent of American adults support abortion rights.

Some activists suspect that some Republican presidential candidates are paying attention to the polling, including when Mike Pence, the former vice president and presidential candidate, said on Friday that he would support a 15-week national ban on the procedure. Other candidates, including Gov. Ron DeSantis of Florida, have supported more restrictive bans, including the six-week one signed in his state.

“It was the right thing to do,” Mr. DeSantis said Friday of signing the law.

The G.O.P. primary front-runner, former President Donald J. Trump, has not gone as far as Mr. Pence or Mr. DeSantis. He takes credit for appointing the Supreme Court justices who overturned Roe v. Wade, but he has so far resisted embracing a federal ban.

As the G.O.P. field assembles, the Biden campaign and the Democratic National Committee will make abortion a primary focus of the president’s re-election effort. This week, the Biden campaign launched an advertisement campaign focused battleground states, including the funding of billboards in Times Square that will highlight Republican efforts to restrict abortion access.

The Democratic National Committee is also encouraging local Democrats to press Republicans to specify what their position is on national bans, believing it will help contrast Mr. Biden’s approach with extremist positions, according to a D.N.C. official.

Inside the White House, Ms. Klein said officials are tracking court cases in individual states and bringing abortion-rights activists together to compare notes on which policies have succeeded.

Still, activists are wary that court victories can be short-lived and do not take away the threat of a wider abortion ban the way legislation would.

In recent months, administration officials have regularly highlighted the stories of women who have been denied emergency medical care when suffering pregnancy loss.

Ms. Harris, who has made several trips and delivered speeches in defense of abortion rights, has frequently introduced medical care providers at her events to bolster the argument that the decision to end a pregnancy is a private one and not to be toyed with by local politicians.

Jill Biden, the first lady, has also been enlisted in the effort. On Tuesday, she hosted a group of women in the Blue Room of the White House and asked them to share their stories. One of the women, Dr. Austin Dennard, a physician in Texas, said she was forced to travel out of state for an abortion when her fetus was diagnosed with anencephaly, a condition that causes a baby to be born without parts of the brain and skull.

Another, a Houston-based Democratic campaign worker named Elizabeth Weller, had gone into labor at 18 weeks and was directed to go home until she developed an infection so severe that a hospital ethics panel allowed a doctor to end the pregnancy.

“Joe is doing everything he can do,” the first lady told the group.

Mini Timmaraju, the president of the abortion rights group NARAL Pro-Choice America, agreed that the Biden administration is “doing everything they can,” but she said the limitations are real.

“We have to give them a pro-choice majority Congress,” she said. “That’s it. They’ve done everything they can up until that point, but without the support of Congress, they are limited and we are limited in what we can do.”