A candidate to become the Republican nominee in Tennessee for Senate has had her advert rejected by Twitter for paid promotion over "inflammatory" remarks on abortion.
Marsha Blackburn says in the video that she "stopped the sale of baby body parts", referring to the sale of foetal tissue for medical research.
Blackburn's announcement ad to take over from retiring senator Bob Corker was rejected because it was "deemed an inflammatory statement that is likely to evoke a strong negative reaction", the company told the campaign, according to the Associated Press.
A Twitter spokesperson confirmed to IBTimes UK that the promoted tweets were suspended for violating Twitter's advertising rules but stressed that the account was not suspended, nor were normal tweets including the video.
Blackburn will not be able to pay to promote it on the social media site unless the offending remark is removed.
In the video, Blackburn describes herself as a "hardcore, card-carrying Tennessee conservative" and "politically incorrect and proud of it".
Blackburn is now using the incident as a way to galvanise followers, urging supporters to share the video to "join me in standing up to Silicon Valley".
"Twitter provides a platform for its users to share and receive a wide range of ideas and content, and we greatly value and defend our users' ability to express themselves." A spokesperson for the company said.
"Advertisers on Twitter have access to a wide range of targeting option to promote their Tweets to a wider audience. Because of this, advertisers on Twitter have the power to reach an audience beyond the users who choose to follow their account."
Twitter has faced accusations of bias in the past as it tows the line between keeping abusive people off the platform and upholding freedom of speech.
Many on Twitter itself remarked that the move was bound to embolden conservatives and act as a boost to Blackburn. "Twitter just gave Marsha Blackburn a gift," Arthur Schwartz tweeted.
Former White House Press Secretary Sean Spicer accused Twitter of continuing a "campaign against @GOP". While LA Times reporter, Matt Pearce described the move by Twitter as "walking face-first into a wall of swords".
It's not the only recent moment that Twitter has found itself answering difficult political questions with both Twitter and Facebook facing calls to provide more information to US lawmakers over accusations the platforms were used by Russia to spread misinformation and propaganda during the 2016 presidential election.