A group of disgruntled Republicans has questioned if the Texas governor, Greg Abbott, used political influence to pull a TV ad criticising his handling of the coronavirus pandemic.

According to a statement issued on Sunday, the Lincoln Project was told the ad, Abbott’s Wall, was being pulled just 10 minutes before it was due to air on ESPN during a nationally televised football game between the University of Texas and Rice University on Saturday night.

The 60-second slot, which the Lincoln Project said cost $25,000 and was approved by ESPN lawyers, blames the Republican governor for more than 60,000 Covid deaths in the state, against a backdrop of images of the US southern border wall.

“If Governor Abbott wants to build a new wall, tell him to stop building this one,” the message says, showing a wall constructed from coffins.

Wood from caskets of all the Covid-19 victims in Texas would stretch 85 miles, the ad claims. It remains watchable on YouTube.

“We were told it was a ‘university-made decision’” to pull the ad, the Lincoln Project said in a press release. “Did Greg Abbott or his allies assert political influence to ensure the advertisement was not broadcast?”

Abbott is an alumni of the University of Texas and appoints members of its board of regents, the Dallas Morning News reported.

The newspaper said neither Abbott nor university officials responded to requests for comment. Neither the governor nor the university immediately responded to messages from the Guardian.

The Lincoln Project was formed by Republican activists and strategists during the Trump administration. It supported Joe Biden in the 2020 election and has continued to attack allies of the former president.

Last week the group blasted the governor of Florida, Ron DeSantis, a Trump loyalist tipped to make a run at the Republican presidential nomination for 2024, as “the worst governor in America”.

The Lincoln Project has faced controversy of its own. In February, for example, it distanced itself from co-founder John Weaver, who was alleged to have made sexual advances to males as young as 14.

On Sunday, the group said it intended to file a public records request with the University of Texas to see if Abbott’s office influenced the decision to pull the ad.

“Instead of focusing on the task of keeping Texans safe from the coronavirus pandemic, it appears Abbott and his advisers are focusing their time and energy on censoring their political opponent,” a statement said.

“We’re not finished with Governor Abbott.”