Sen. Claire McCaskill (D-Mo.), seen here in a file photo, faces a difficult reelection contest next year. (Alex Brandon/AP)

Liberal groups are seizing on Republican attempts to roll back health coverage and limit access to birth control, as they seek to galvanize women voters ahead of next year’s midterm elections.

Organizations such as Planned Parenthood Action Fund and Emily’s List believe the Trump administration handed them a potent political issue Friday when it carved out wide exceptions to the Affordable Care Act’s promise of no-cost contraception. Activists plan to link this action to congressional Republicans’ repeated attempts to undercut the ACA in ways that could have caused millions to lose health insurance, as part of a broader strategy focused on defeating moderate GOP members and buttressing vulnerable Democrats.

“As millions of women watch this administration take away fundamental health care like birth control, they’re also paying attention to all those members of Congress who are not standing up to fight for them,” said Erica Sackin, political communications director for Planned Parenthood Action Fund, in a phone interview.

Democrats are eager to capi­tal­ize on women’s anger toward the Trump administration and congressional Republicans in a cycle that could be punishing for Democratic Senate incumbents. While Democratic candidates could make some gains in the House, the party is defending 10 Senate seats in states won by President Trump — five in states he won by double-digits. By framing their message around health-care access, strategists hope to appeal to women voters who might not see themselves as part of the anti-Trump “resistance,” but who opposed GOP health-care proposals this spring and summer.

Activists said the 2018 cycle is ripe for strong, pro-woman messaging in light of mounting sexual harassment scandals like the one engulfing Hollywood mogul Harvey Weinstein, which remind women of their continued vulnerability to discrimination, and Trump’s poor approval ratings with female voters.

President Trump's rollback of contraception coverage is rallying his opponents, who hope to harness the energy of the strong pro-woman activism to win back congressional seats in 2018. (Jenny Starrs/The Washington Post)

Trump’s latest change to the birth-control policy, which gave employers greater leeway not to cover contraception in workers’ health plans, dovetails neatly with those themes.

“This administration has really made an effort to roll out an anti-woman agenda,” said Vanessa Cardenas, director of strategic communications for Emily’s List. “We want to make sure women understand what’s at stake. . . . Women are realizing more and more how their rights are under threat.”

Kaylie Hanson Long, national communications director for NARAL Pro-Choice America, said women’s rights and health care rank among the top issues for key voters in 2018.

“We’ll absolutely be reminding voters which candidates stand with Donald Trump and which candidates stand with women,” Long said in an emailed statement.

National survey data appears to be on Democrats’ side.

In a June poll, the Kaiser Family Foundation found two-thirds of Americans supported the ACA’s requirement that private health insurance plans cover the full cost of birth control, including over half of Republicans and larger majorities of independents.

Smaller majorities of adults opposed allowing exceptions for employers with religious objections, 53 percent, or moral objections, 55 percent, to contraception.

Republicans are showing signs they will rebut criticism by attacking Democrats’ support for a single-payer health-care system.

“Any conversation on health care begins and ends with House Democrats’ full embrace of single-payer,” Jesse Hunt, the National Republican Congressional Committee’s national press secretary, in an emailed statement. “The promise of massive tax increases and a reduction in the quality of health care one receives is sure to be a drag on their electoral prospects.”

A request for comment from the National Republican Senatorial Committee was not returned.

Democrats see an opportunity to use their health-care message in Nevada, where an original co-sponsor of the Cassidy-Graham bill — Sen. Dean Heller (R-Nev.) — is defending his seat and represents their best chance at picking off a GOP incumbent.

Hillary Clinton won the state by 2.4 points in November, and strategists noted that freshman Sen. Catherine Cortez Masto (D-Nev.) won after repeatedly attacking her GOP opponent for his conservative abortion stance and votes to defund Planned Parenthood. Groups such as Planned Parenthood Votes and Emily’s List described her repeatedly as a “champion” for women’s health and rights.

Heller’s support for Senate Republicans’ latest failed health-care bill could come back to haunt him in the race. The first-term senator was one of four original co-sponsors of the legislation, which a majority of Americans opposed in September’s Washington Post-ABC News poll.

Rep. Jacky Rosen (D-Nev.), who launched her bid for Heller’s seat this summer, is already using the health-care and birth-control issues as cudgels.

“This puts basic, fundamental health care at risk for 62 million women,” Rosen tweeted Friday after the administration’s birth-control announcement. “It’s anti-women’s health, plain & simple. Unacceptable.”

A tougher test could be Democratic Sen. Claire McCaskill’s bid for reelection in Missouri.

The two-term senator has benefited in the past from Republican ham-handedness on women’s health: In 2012, Republican Rep. Todd Akin (Mo.) was considered a viable challenger to McCaskill before saying that victims of “legitimate rape” rarely become pregnant. The comment drew backlash from both parties and pushed McCaskill far ahead with women voters. She won the race, 54.8 percent to 39.1 percent.

This time, things might not be so simple. Missouri went for Trump by 18.5 points in November, and the president has repeatedly urged voters to push her out next year.

McCaskill took issue with the Trump administration’s birth-control decision on Friday.

“Folks of every political stripe and every faith can agree on the goal of reducing the number of unintended pregnancies and abortions,” she said in a statement. “Well, the best way to do that is to expand access to birth control, not restrict it.”

At a town hall event on Wednesday, McCaskill earned enthusiastic applause from the mostly female audience when she talked about access to birth control.

She later told reporters that the Trump administration is “sabotaging” Obamacare’s insurance exchanges.

“They own health care 100 percent right now,” McCaskill said of Republicans. “And I think they’re underestimating the political blowback they’re going to get if they don’t get busy and help us do just the bare minimum to stabilize these exchanges.”

Liberal groups are also optimistic about the 23 Republican congressional districts won by Hillary Clinton in 2016. From southern California to the suburbs of Philadelphia, Houston and Phoenix, GOP lawmakers are poised to see attacks from the left on health care.

“Those seats are fertile ground for us,” said Julie McClain Downey, director of campaign communications for Emily’s List. “Defunding Planned Parenthood, rolling back the birth-control mandate — we will continue to amplify those issues and draw voters’ attention to them for the next year.”

Despite repeated tries, the GOP’s seven-year promise to repeal and replace the health-care law died in large part because of two Republican women — Sens. Susan Collins (R-Maine) and Lisa Murkowski (R-Alaska) — and their concerns about defunding Planned Parenthood, threatening health-care coverage for Medicaid recipients and loosening requirements that insurers cover maternity care and other vital services for women.

Women callers also dominated the phone lines on Capitol Hill as opponents of the health-care bills urged them to weigh in, according to congressional aides.

“They are definitely paying attention,” Cardenas said. “For many of them, they are the ones that are dealing with people who might be sick in their families. They are the ones who will have birth control taken away from them. So they are feeling this impact directly.”

Ed O’Keefe and Scott Clement contributed to this report.