Originally Published: 22 OCT 22 10:32 ET

Updated: 22 OCT 22 10:38 ET

By Em Steck and Andrew Kaczynski, CNN

(CNN) -- A political robocall made to tens of thousands of Georgians thanked a vulnerable congressional Democrat and the Democratic nominee for governor for protecting the rights of "birthing persons" to "have an abortion up until the date of birth" -- targeting abortion rights tension in the competitive races.

The calls, which used polarizing language popular with Democratic activists, are made to sound like they are in support of Democratic Rep. Sanford Bishop and gubernatorial nominee Stacey Abrams -- but Democrats involved in the races allege that the call, uncovered by CNN's KFile, is the work of Republicans.

The call says it is done by a group called American Values -- groups operating under that name or similar ones have said they are not behind the call.

Bishop, who has served in Congress for 30 years, faces Republican Chris West in the race for Georgia's 2nd Congressional District, one of the only competitive House races in the state.

The Abrams campaign and the Democratic Congressional Campaign Committee, which supports Bishop's race, said they did not pay for the robocall. Bishop's campaign declined to comment on the record.

The robocall is narrated by a woman who gives her name as Jill and her pronouns as she/her and continues to say people who identify as women are under attack in the state.

"This is Jill, and my pronouns are she/her," she says. "I'm sure you'll agree with me that people that identify as women are under attack, not just in Georgia, but throughout our country. Georgia is lucky to have Stacey Abrams and Sanford Bishop fighting for our abortion rights."

The call goes on to say Bishop and Abrams support abortion until the moment of birth. Abrams has campaigned that she does not believe in any government restrictions on abortion, calling it a medical decision not beholden to "arbitrary" timelines. Bishop has voted in the past to ban late-term abortion procedures, indicating some support for restriction, and has said that abortion should be rare, legal and safe and available in cases of rape, incest or to protect the life or health of a woman.

"While some elected officials are trying to limit abortion rights to six months or even five months after conception, we are so lucky to have Stacey Abrams and Sanford Bishop fighting to protect our right to have an abortion up until the date of birth," the narrator of the call says. "Would you please take a moment to call Stacey Abrams or Sanford Bishop and thank them for standing up for women's right to abort their babies up to the point of birth."

"Government needs to stay out of the reproductive rights of birthing persons," says the narrator, Jill.

The robocall ends by saying it was "paid for by American Values and not authorized with any candidate or candidate's committee" -- but several groups who operate under that name or similar names denied to CNN they were behind the call. And there is no political action committee registered by that name in Georgia.

The call reached approximately 43,000 phones from Friday October 14 through Sunday October 16, according to data from the anti-robocall app Nomorobo.

The message fails to identify who paid for the call in the introduction and give a call back number, which violates rules from the Federal Communications Commission for autodialed or prerecorded voice political campaign calls.

The October robocall also invites listeners to press one and two to leave a message for Abrams and Bishop, respectively. If a user presses two, they are redirected to Bishop's Albany district office. But when a user presses one, the call redirects to the private number of the chair for the local Democratic committee, Sandra Sallee. Sallee called the ploy a "dirty" trick in a phone interview and said she was subjected to harassing phone calls.

Unclear origins

CNN's KFile reached out to nearly a dozen active federal PACs with "American Values" in their name. Several PACs told CNN they have never used robocalls for messaging and have no plans to; others did not respond to CNN's comment request.

"Robocalls are kind of a funny political tactic in so far as they have an almost perfect record of never working," said Donald Green, a professor of political science at Columbia University.

Green said the "fairly unanimous conclusion" is that they don't seem to affect voter turnout or vote choice but are often used because they are very inexpensive. He suggested that the tactic could have been used to generate media attention to the race.

"It's pretty unusual to have something that is kind of, you know, wolf-in-sheep's-clothing-type tactic," said Green. "It's not unheard of in American politics because nothing is unheard of, but it's rare."

On Thursday, another mysterious robocall littered with falsehoods was made to Georgia voters with a similar modus operandi, but this time it solely targets Bishop.

"Congressman Bishop is the only candidate with 100% rating with Planned Parenthood and will defend the right to an abortion up to nine months. Do not let Republican Chris West win," a female narrator says.

According to data from Nomorobo, this robocall reached 41,000 phones and there is some overlap between the recipients of this call and the one targeting Abrams and Bishop.

The call failed to disclose who was behind it at the beginning and end of the call. When CNN tried to call the number, an automated message said that "this number is temporarily unavailable. Please try again later."

Campaign and committees blast call

In a statement to CNN, Abrams' campaign spokesperson Alex Floyd said, "This disgusting and false attack is a new low for the right wing — and comes as misrepresentations and outright lies that have become a feature of the Kemp campaign. Stacey Abrams has been clear about her support for limitations on abortion in line with Roe and Casey. Now it's time for Brian Kemp to clearly condemn this false robocall and start answering Georgians' questions about his extreme anti-choice record."

Abrams, who once opposed abortion rights, said last month that abortion is "a decision that should be made between a woman and her doctor. That viability is the metric. And that if a woman's health or life is in danger, then viability extends until the time of birth, but women do not make this choice lightly."

Abrams added that no one believes there should not be a limit, but that "the limit should not be made by politicians who don't believe in basic biology or, apparently, basic morality."

A spokesperson from the Kemp campaign, Tate Mitchell, said they were not responsible for the robocalls.

The Bishop campaign declined to comment to CNN.

The DCCC said through spokesperson Monica Robinson, "This misleading robocall -- paid for by a shady outside interest group -- is what desperation smells like. Resorting to lies to win an election is proof that Chris West can't win honestly or on his own merits. If West has any integrity at all, he'll denounce these robocalls and call on his special interest backers to stop lying to Georgians."

Bishop, a 15-term moderate Democrat, has in the past advocated and voted for some late-term abortion restrictions, and recently reiterated his support for abortion rights. "These personal health care choices should ultimately rest with a woman, her God and her doctor—not with politicians in 50 different state legislatures," Bishop said in a statement after the Supreme Court overturned Roe v. Wade.

West's campaign did not respond to CNN's requests for comment.

Similar call tried to sway the GOP primary

This is not the first time a robocall spouting specious claims has occurred in Georgia's 2nd Congressional District in this election cycle.

In June, the local newspaper the Ledger-Enquirer reported that robocalls were being sent to households in the district that appeared to be affiliated with Republican candidate Jeremy Hunt's campaign, but the underlying message was meant to drive support away from Hunt, a Black former Army captain.

One June robocall noted it was time to "celebrate Black independence" and "modernize" the Republican party by supporting Hunt. "We can leave the old ways of the Republican Party in the past and build our party back better," the narrator said, a nod to Biden's "Build Back Better" slogan. "No more attacks on our capital, no more divisive language from a former President."

That robocall also did not identify who paid for it, and both Hunt and West accused the other's campaign and the super PACs supporting them of sending the call.

One PAC that supported Hunt in that primary is called "American Values First," a name partially invoked in the October robocall targeting Bishop and Abrams.

American Values First is one of the PACs CNN reached out for comment to ask if they are responsible for the October robocall. The treasurer and spokesperson for the PAC, Joel Riter, said that the PAC had nothing to do with the robocalls and has not spent any money in the race for the general election.