One of the nation's leading pro-life groups is celebrating its work toward toppling Republican Rep. Renee Ellmers this week, and now the Susan B. Anthony List is preparing to stop Hillary Clinton from becoming the next president.

On Tuesday, Ellmers became the first incumbent member of Congress to lose in a 2016 primary. Ellmers was soundly defeated by fellow GOP Rep. George Holding as a redrawn district pitted two sitting members of the House against one another. Holding scored 16,999 votes, while Ellmers received 7,527.

Conservative and Republican opposition to Ellmers had been intensifying for years, as she routinely sided with Republican leaders and failed to fight President Obama's unilateral immigration action. But it was her actions in January 2015 that put her in the cross-hairs of the Susan B. Anthony List and other pro-life activists.

"Congresswoman Ellmers led the charge to derail the Pain Capable Unborn Child Protection Act. This was common-sense legislation to stop abortion after five months. It has majority support among Americans. Women support this bill in higher numbers than men. It was scheduled for a vote on the day of the March for Life 2015," said Susan B. Anthony List Communications Director Mallory Quigley.

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Read the tested and proven strategies to defeat the abortion cartel in "Abortion Free: Your Manual for Building a Pro-Life America One Community at a Time."

Quigley told WND and Radio America Ellmers began undermining the bill weeks earlier.

"Congresswoman Ellmers started to make a fuss in the media, saying that millennials don't support this issue," Quigley said. "They don't support this legislation, and this shouldn't be among Republicans' top few legislative priorities."

As the vote got closer, Ellmers then amended the basis of her opposition. She spoke out against an abortion exception beyond 20 weeks for rape victims because she did not want those patients to be required to show a police report alleging the rape prior to proceeding with the abortion. Backers of the provision pointed out that no such paperwork was required prior to 20 weeks of pregnancy.

Quigley said Ellmers not only succeeded in scuttling the vote but triggered fierce media criticism of the bill.

"She contributed to this media firestorm, taking attention away from the horrific reality we were trying to draw America's eyes to: the fact the U.S. is one of only seven nations to allow abortion on demand after five months," Quigley said.

As a result, the Susan B. Anthony List, which works to elect pro-life women to public office, took an unprecedented step.

"Because that betrayal was so profound, we had to take action and endorse against her," Quigley said. "It was the first time in our history that we've endorsed a pro-life man over a pro-life woman in a Republican primary."

Listen to the WND/Radio America interview with Mallory Quigley:

It wasn't just an endorsement. The group also blitzed North Carolina's second congressional district, going door-to-door to tell thousands of GOP voters why Ellmers was unacceptable to them. Quigley said their work made a big difference.

"Almost 40 percent of the people who originally said to the activists that they were supporting Renee Ellmers changed their minds and said they were less likely to vote for her after learning about her role in derailing the pain capable bill," Quigley said.

She said taking the time to speak with voters is quickly becoming the most effective campaign tool.

"You can't really measure what the impact of a TV ad is, especially in the age of NetFlix and DVR," Quigley said. "For us to know that we actually reached 12,571 people by Election Day was a powerful statement for the pro-life movement. This is where we thrive, in person-to-person interaction."

When Holding's overwhelming victory was secured, Quigley and her colleagues rejoiced.

"We could not stand for what she did back in January (2015) and the damage she caused to the pro-life movement, so we were glad to see her defeated on Tuesday," Quigley said.

Now the Susan B. Anthony List turns its attention to the general election, in races all over the nation and in the race for the White House.

Read the tested and proven strategies to defeat the abortion cartel in "Abortion Free: Your Manual for Building a Pro-Life America One Community at a Time."

On Tuesday, Hillary Clinton secured the delegates needed to make her the presumptive Democratic presidential nominee. In her speech, she claimed the legacy of the women who fought for women's suffrage, which, of course, includes Susan B. Anthony.

"Susan B. Anthony, if she were alive today, would not recognize the position that Hillary Clinton has taken as being the pro-woman feminist," said Quigley, who said Clinton is not the pro-woman candidate because she couldn't care less about women who disagree with her on abortion.

"Hillary is all about being her kind of woman," she said. "She does not leave open the possibility that there is a majority of women in America who think that it's not OK to build up their rights on the broken rights of their unborn children."

During the Republican primaries, Susan B. Anthony List President Marjorie Dannenfelser joined several other pro-life leaders in denouncing Donald Trump as not a reliable pro-life candidate. But with Hillary Clinton and pro-choice Libertarian Gary Johnson as the only other options drawing any support, Quigley said the group's tune on Trump has changed.

"Donald Trump has made very firm commitments to the pro-life movement that he has reiterated several times," Quigley said. "He said that will nominate justices to the Supreme Court who will be pro-life. He actually used the term 'pro-life,' which is to go a step further than others who would just say a 'strong constitutionalist.'''

He has also made commitments to support defunding Planned Parenthood and passage of the Pain Capable Unborn Child Protection Act.

While Trump was not the group's preference earlier this year, Quigley said the match-up with Clinton makes the decision a no-brainer.

"He's certainly said some things that were indefensible, but I think ultimately what matters is policy and the court," Quigley said.

"[Clinton] wants to repeal the Hyde Amendment, which would be the most pro-abortion position that any politician has ever taken, even to the left of Barack Obama, to force taxpayers to fund abortion on demand," she said. "There may be some questions about Donald Trump, but Hillary Clinton is a sure thing."