Rep. Renee Ellmers (R-N.C.) and Republican vice presidential candidate, Rep. Paul Ryan (R-Wis.) answers questions during a campaign event at Partnership for Defense Innovation in Fayetteville, N.C., on  Aug. 23, 2012. (AP Photo/Sara D. Davis)

Updated at 5:41 p.m. on 1/23

Rep. Renee Ellmers (N.C.) was perhaps best known outside her district as the Republican who beat American Idol sensation Clay Aiken. Less than three weeks into the 114th Congress, she has a new claim to fame, as Public Enemy No. 1 for conservative activists.

Ellmers has drawn an intense backlash from social conservatives infuriated by her involvement in the push to sink or at least delay a bill that would have imposed a ban on abortions after the 20th week of pregnancy, despite supporting a similar measure in the past and pledging to do so again. Coming just days after she infuriated the political right by voting against a bill designed as a sharp retort to President Obama's executive actions on immigration, the maneuvering made her a national focal point of conservative angst and raised questions about whether she would survive a Republican primary in 2016.

The third-term congresswoman was a no-show as about four dozen activists gathered in front of her office Thursday afternoon to voice their frustration. Sporting anti-abortion buttons, scarves and sweatshirts, the group arrived from the "March for Life," an annual protest falling on the anniversary of the landmark Roe. v. Wade Supreme Court decision.

They weren't happy.

"Her lack of leadership is very troubling. And it is a let-down to the pro-life movement," said Brandi Swindell of Boise, Idaho.

Rev. Patrick Mahoney, the head of the Christian Defense Coalition, offered a broader critique of Republican leaders for pulling the bill.

"They could not have sent a worse signal to the pro-life community. And they in essence are getting us to ask the question: Why should we work for Republican candidates?"

Ellmers' staff braced for the backlash, extending a preemptive olive branch in the form of a bucket filled with bottled water and cans of Cheerwine soda. Aides greeted protesters at the door, agreeing to hear their concerns and respond to them. But the absence of the congresswoman, who mostly avoided the media on Thursday, angered some activists.

"Sounds like a kiss off!" responded one, upon learning the news that Ellmers was on an unspecified, pre-arranged trip to another state with other members of Congress. Another declared that she was "not leaving" until she got to speak with Ellmers.

"We know people are angry. That's been made clear. We get it. You're angry and you're upset. She'll be made aware of that," Ellmers' legislative director Mitch Vakerics told the crowd.

The protesters voiced concerns about what Ellmers recently told National Journal about abortion: "The first vote we take, or the second vote, or the fifth vote, shouldn’t be on an issue where we know that millennials — social issues just aren’t as important” to them.

The hastily arranged protest, which was mostly cordial, was a microcosm of the broader anger Ellmers has stoked. On Wednesday, conservative blogger Erick Erickson mockingly tweeted "I'm sorry Clay Aiken lost," a reference to Ellmers' 2014 reelection.

Ellmers stoked widespread confusion when she reversed course on the anti-abortion bill. "To clear up any misinformation, I'll be voting tomorrow to support H.R. 36 -- The Pain-Capable Unborn Child Protect Act," she tweeted Wednesday afternoon.

The congresswoman issued a statement Thursday explaining that she will continue to work with her colleagues to "address our concerns" with the language of the measure, toward the ultimate goal of "bringing this legislation to the House floor for a vote."

Ellmers voted for a similar version of the bill two years ago. But at a closed-door meeting with Republicans on Wednesday, she voiced her concerns, according to several attendees.

In a speech on the House floor Thursday, Ellmers sought to emphasize her opposition to abortion, illustrating the difficult balance she is trying to strike.

"I believe in the sanctity of human life and that life begins at conception and ends at death," she said, voicing her support for a less controversial measure that would bar federal money for abortions.

For some conservatives, Ellmers' abortion position was a here-we-go-again moment reminiscent of her vote against a Republican plan to block funding to Obama's executive actions on immigration, including his move to head off the deportations of millions of undocumented immigrants. The vote reiterated her reputation as a moderate on immigration.

On his blog Thursday, Erickson wrote: "Hopefully, between this and her immigration betrayal, someone ... will begin a campaign to unseat her."

Carter Wrenn, Ellmers' 2010 campaign consultant, estimated that he must have received e-mails from six people in recent days wanting to talk about fielding a primary challenger.

"It's pretty stirred up down here," said Wrenn, who said he has heard that Chatham County Republican Party Chairman Jim Duncan is mulling a bid.

Ellmers' latest moves on immigration and abortion are a sharp contrast to the initial perception of her in 2010, when she came from seemingly nowhere to defeat a once-entrenched Democratic incumbent. She won the GOP primary that year without any fanfare, as few thought anyone could knock off 14-year veteran Democrat Bob Etheridge. But by September 2010 her struggling campaign latched onto the proposed construction of a mosque near the site the twin towers of the World Trade Center once stood.

“The terrorists haven’t won, and we should tell them in plain English: no, there will never be a mosque at Ground Zero,” she said in an ad that compared the proposal to "victory mosques."

Those ads and her background led many to presume that Ellmers would fit in with the other tea party renegades swept to power in 2010. A registered nurse with no political experience, she decided to challenge Etheridge after questioning him about the new health-care law. Sarah Palin endorsed her, but she received marginal support from Republicans in Washington – but then after a 17-day recount, Ellmers had won by 1 percentage point, leading author Robert Draper to describe her and a few other neophytes as “naked orphans on the doorstep of power.”

However, within months of taking office, the constellation of outside conservative groups that form the tea party’s establishment in Washington took notice of her drift toward the leadership. By the summer of 2011, Ellmers became a regular at leadership press conferences led by Speaker John A. Boehner (R-Ohio) and Majority Leader Kevin McCarthy (R-Calif.), promoting their approaches to a budget bill that staunch conservatives considered a sellout.

During Thursday's vote, Ellmers was seen having lengthy conversation on the House floor with Rep. Cathy McMorris Rodgers (Wash.), the fourth-ranking House Republican.

Her lifetime voting percentage with Heritage Action, the offshoot of the conservative Heritage Foundation think tank, is just 55 percent.

By 2013, the anti-tax Club for Growth decided to try to draft a challenger to Ellmers in the GOP primary out of frustration with her record on fiscal issues. It was part of an online gambit called “Primary My Congressman." But her opponent turned out to be weak, and she won with less than 59 percent.

Some Republicans defended Ellmers Thursday, like Rep. Charlie Dent (Pa.), a moderate Republican who has criticized the pressure conservatives have applied on the GOP's agenda in the new Congress.

"I think it's unfair because she pointed out a problem with the bill," said Dent of the backlash Ellmers is facing, adding that many others "expressed the same concerns."

After the decennial redistricting process, Ellmers's central North Carolina district became more conservative, further protecting her from the threat of a Democratic opponent beginning in 2012. But the map may work against her in 2016, with activists already talking about drafting a competitive challenger.

"We're just going to hold her accountable for it," said Tami Fitzgerald, a conservative activist from Raleigh.

Ed O'Keefe contributed.