Abortion opponents rallying by the thousands Friday in Washington at the annual March for Life have lost some political battles lately but won a string of court victories, thanks in part to a diverse coalition challenging a contraception mandate in the health care overhaul.

For-profit businesses, state attorneys general and educational institutions are among more than 100 plaintiffs who have mounted some 40 lawsuits challenging the mandate, according to the Becket Fund for Religious Liberty, a nonprofit legal institute that has played a leading role in the suits. With lower courts in dispute over the mandate, both sides agree the issue will almost inevitably be settled by the Supreme Court.

The mandate requires employer-sponsored health care plans to cover contraception, including intrauterine devices and emergency birth control drugs that many religious employers equate with abortion. The Obama administration offered a narrow exemption for religious organizations and required insurers, not employers, to pay for the services. However, opponents remain unsatisfied.

Most of the mandate’s challengers are nonprofits such as Catholic educational institutions, hospitals, and archdioceses. But Protestant institutions have also sued, as have several for-profit businesses, including the arts-and-crafts chain Hobby Lobby Inc., based in Oklahoma City. The fight has drawn in Washington players, such as the Becket Fund, that do not typically focus on abortion but that regard the mandate as a violation of religious freedom.

“We’re trying to shape the law around religious liberty and not jump into these culture war issues,” said Becket Fund President William Mumma, a former Wall Street executive. “I don’t see it by any means as a contest over abortion.”

The white shoe law firm of Jones Day has also deployed a team of lawyers around the country, including a half-dozen in its Washington office, to defend Catholic dioceses and educational institutions suing the federal government. Other leading players representing the plaintiffs include the anti-abortion group Americans United for Life, the Scottsdale, Ariz.-based Alliance Defending Freedom and the American Center for Law and Justice.

“I think you’re seeing this unique coalition coalescing on this issue because of the scope of what’s at stake,” said Jay Sekulow, chief counsel at the American Center for Law and Justice, a conservative legal services nonprofit. The legal fight combines religious liberty and conscience as well as reproductive health issues. Sekulow added, “It’s a broad class of plaintiffs that are impacted by this.”

Sekulow’s group has filed four direct challenges on behalf of for-profit companies against the Department of Health and Human Services, obtaining injunctions in all three.

Many of the tax-exempt groups filing suits have found themselves in a holding pattern in the courts, in part because the administration has agreed to delay implementation of the mandate for those groups until August of this year while it crafts compromise regulations, Becket Fund general counsel Kyle Duncan said. But in 14 cases involving for-profit businesses, nine lower courts have given the plaintiffs preliminary injunctive relief, according to Duncan.

“We believe that the owners  . . .  have a claim of religious liberty, particularly when you’re talking about a closely held family business,” and that the mandate violates the 1993 Religious Freedom Restoration Act, Duncan said.

Some of the legal institutes challenging the mandate have considerable financial heft behind them. Americans United for Life, which has raised its profile since moving its headquarters from Chicago to Washington in 2009, had a $4 million budget in 2010, tax filings show, up from about $1 million in 2007. The American Center for Law and Justice had a $16.7 million budget in 2010, according to tax records. And the Alliance Defense Fund, a socially conservative nonprofit and grant-making organization, had a budget approaching $34 million that same year.

Defending the mandate are the American Civil Liberties Union and a long list of women’s health providers and advocates, including the National Women’s Health Network, the Guttmacher Institute and the doctor-led Physicians for Reproductive Choice and Health.

“Regardless of whether you are a for-profit or a not-for-profit, taking a job isn’t the same as joining a church,” ACLU Senior Staff Attorney Brigitte Amiri said. “So organizations and businesses that operate in the public sphere should abide by public rules.”

Allowing companies such as the Hobby Lobby, which has some 13,000 employees, to dictate health care coverage would have practical implications for women and set “a very disturbing precedent,” she added.

The legal battle has largely failed to capture the public’s attention but reflects the cross-currents shaping the abortion debate on the 40th anniversary of the Supreme Court’s Roe v. Wade ruling that legalized abortion.

Public opinion on the issue has shifted remarkably little over the decades, experts say, with a majority of Americans supporting the legal right to an abortion but also accepting a variety of restrictions. At the same time, new drugs such as emergency contraception have created legal and medical ambiguities.

“We’re really blurring the line between contraception and abortion here” when it comes to emergency contraceptives, said Anna Franzonello, staff counsel at Americans United for Life.

An earlier version of this article misspelled the name of Jay Sekulow, chief counsel at the American Center for Law and Justice.