Updated

In an effort that has produced heated public feuds as well as significant changes in proposed health care legislation, religious leaders are zeroing in on followers of their faith in Congress to make sure that taxpayer money will not be used to fund abortions.

The latest confrontation comes between Rep. Patrick Kennedy, D-R.I., an abortion-rights supporter, and Roman Catholic Bishop Thomas Tobin, who asked Kennedy not to receive Holy Communion if he maintained his position.

The tension is palpable as senators prepare to take up a version of legislation that pro-life leaders say does not provide the same assurances as the version that passed the House early this month. Catholic leaders were considered key in pushing for the restrictions in the House bill.

Richard Doerflinger, associate director of the U.S. Conference of Catholic Bishop' Secretariat of Pro-Life Activities, said Monday that his group will "work with senators of both parties" to address their concerns. But his group blasted the Senate health bill on Friday, and Doerflinger said Monday that the conference will oppose it if their concerns are not met.

Here's a look at some of the lawmakers who are at odds with their religious leaders over the issue:

Rep. Patrick Kennedy 

The dispute between Kennedy, son of the late Sen. Ted Kennedy, and Tobin began in October when Kennedy criticized Catholic bishops for threatening to oppose health care reform without restrictions on federally funded abortion. Tobin demanded an apology and requested a meeting with Kennedy, but that meeting fell through. Tobin then wrote a public letter calling Kennedy's position "scandalous" and "unacceptable."

The latest chapter in the dispute came over the weekend, when Kennedy told The Providence Journal that Tobin instructed him not to take Communion and instructed other priests not to give it to Kennedy either. Though Tobin denied banning Kennedy from receiving Communion elsewhere, he said he did ask Kennedy to stop receiving Communion in 2007.

"He attacked the church, he attacked the position of the church on health care, on abortion, on funding," Tobin told The Associated Press on Sunday.

But Kennedy, a member of the most prominent Catholic family in American political life, has earned some support in his stand against the church.

Catholics for Choice issued a statement Monday applauding Kennedy and describing Tobin as part of a "small minority of bishops" trying to "intimidate" Catholic lawmakers.

"Despite what this minority of bishops has done -- and it is worth noting that the majority of bishops do not seek to use the sacraments as political weapons -- prochoice Catholic policymakers continue to stand by their consciences," the statement said.

House Speaker Nancy Pelosi 

Pelosi has a long history of conflict with the Catholic Church.

But the church's intervention this time around may have helped persuade the California Democrat, who is Catholic, to allow a game-changing amendment.

Before the House passed its health care bill, representatives for Catholic bishops huddled with top officials in Pelosi's office to discuss the language. Cardinal Theodore E. McCarrick, the former archbishop of Washington, also called Pelosi to discuss abortion restrictions with her personally.

In the end, an amendment from Rep. Bart Stupak, D-Mich., to impose tough restrictions on federal funding for abortion coverage passed along with the overall health care bill. And the bishops are taking credit.

"It was a good example of how we as a conference can work together to have a positive influence on legislation," Bishop William Murphy, chairman of the U.S. Conference of Catholic Bishops Committee on Domestic Justice and Human Development, told the Catholic News Service, pledging that the conference would remain "vigilant" on the Senate side.

But the bishops' harmony with Pelosi may be temporary.

William Donohue, president of the Catholic League, told FoxNews.com that he expects Pelosi to try to strip out the Stupak language in conference committee when differences between the House and Senate versions must be ironed out. Donohue was one of 150 Christian leaders who signed a declaration on Friday reaffirming their opposition to abortion and gay marriage.

Pelosi hasn't shied away from confrontations with the church. She was rebuked by the archbishop of Washington last year after she said in an interview that the church had been inconsistent on its abortion position over the years. At the same time, the archbishop of Denver warned then-vice presidential candidate Joe Biden not to take Communion. Pelosi later met privately with Pope Benedict XVI at the Vatican. The Vatican released a statement at the time saying the pope spoke with Pelosi about "the Church's consistent teaching on the dignity of human life from conception to natural death."

Rep. Michael Capuano 

Capuano, D-Mass., has also bucked leaders of his Catholic faith to take a firm stand in favor of abortion rights as the health care debate proceeds. He told FoxNews.com recently that he would "tend to vote against" the final bill if it restricted abortion funding -- though he voted for the House version weeks ago.

Capuano is focusing on abortion in part because it's a big issue in the race for the Senate seat formerly held by Ted Kennedy. Both he and state Attorney General Martha Coakley are playing up their abortion rights credentials in the race for the Democratic nomination.

Capuano, though, made clear that he won't be intimidated by Catholic leaders on the issue.

"I treat them with probably more respect, more deference. But they don't tell me how to vote," he said, according to The Boston Globe.

Rep. Rosa DeLauro 

DeLauro, D-Conn., was among the female Democratic House members outraged by the Stupak amendment. DeLauro reportedly got in a shouting match with Rep. George Miller, a Pelosi ally, after the House speaker announced in early November that she would allow the amendment on the health care reform bill.

But as a Catholic, DeLauro has drawn fierce criticism from inside the religious community.

Deacon Keith Fournier, founder of The Catholic Way, listed DeLauro among those lawmakers "who supported the funding of the continued killing of children in the womb with tax dollars" in a recent online column.

In an interview with the Catholic News Agency, a representative for The National Right to Life Committee blasted a separate amendment offered by DeLauro on the issue of abortion funding as "ludicrous" and "an insult."

Sen. Bob Casey Jr. 

Casey, D-Pa., is known for his pro-life stance but he's not been entirely clear on how forcefully he would come down on the issue in the Senate health care legislation.

Expect the Catholic senator to be a target of religious groups seeking tougher language in Majority Leader Harry Reid's health care bill.

"Bob Casey has had an on-again, off-again relationship with some of the bishops in his state," Donohue said. "I'm sure there's a tremendous amount of pressure on him to make good on this."

Casey told CNSNews.com in early November that he supports an amendment to prohibit federal funding from paying for abortion coverage in health care reform.

But then a few days later, his office put out a statement saying he's not in favor of new restrictions, suggesting he doesn't want to pursue language akin to the Stupak amendment in the Senate.

Galen Carey, director of government affairs for the National Association of Evangelicals, told FoxNews.com that his group is hoping to persuade Casey, and even Reid, to change the abortion language in the Senate bill.

"The current Senate bill is a radical departure from the current U.S. government policy," Carey said.

The Senate bill as written would allow let private insurers that receive federal subsidies to offer plans that include abortion coverage, but the money for abortions is supposed to come from premiums paid by beneficiaries and not from the subsidy money.

The Associated Press contributed to this report.