A liberal group that criticized U.S. Sen. Cory Gardner earlier this year for consistently siding with Senate Republican Leader Mitch McConnell has resurrected itself to urge Gardner to let the president elected in November nominate a new Supreme Court justice.

Cut the Strings CO, a campaign financed by the dark-money nonprofit Rocky Mountain Values, on Tuesday kicked off a $1.5 million TV and digital ad campaign calling on Gardner to stick with the argument he made four years ago, when the Republican declared it was too close to the election to replace a justice who died nine months before Americans voted.

Using footage of Gardner’s 2016 argument against the Senate confirming President Barack Obama’s nominee to fill the vacancy created by the death of Justice Antonin Scalia, the 60-second ad’s narrator says, “Tell Gardner to stand up to Mitch McConnell and Donald Trump — don’t vote to confirm Amy Coney Barrett before inauguration.”

Senate Republicans have laid out a speedy schedule to confirm Barrett, the appeals court judge nominated by Trump on Saturday to fill the vacancy created by Justice Ruth Bader Ginsburg’s death on Sept. 18.

It’s the latest campaign aimed at Colorado voters to focus on the contentious nomination as Democrats attempt to stop Trump and Senate Republicans from cementing a conservative majority on the high court for a generation.

On Monday, he conservative Americans for Prosperity-Colorado said it was rolling out a multi-pronged campaign to urge Gardner and his Democratic colleague, U.S. Sen. Michael Bennet, to confirm Barrett, part of a 10-state effort to pressure senators to get behind the nominee.

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Gardner, who is running for a second term against Democratic challenger John Hickenlooper, announced a week ago that he would back McConnell’s plans to move ahead seating Trump’s nominee despite Republicans blocking Obama’s nomination of Judge Merrick Garland during the last presidential election year.

“Senator Gardner’s flip flop to support filling the Supreme Court vacancy once again shows he is following Mitch McConnell’s lead, not listening to Coloradans,” said Marie Aberger, spokeswoman for Cut the Strings CO. “With Coloradans’ health care on the line if the Affordable Care Act is struck down, Cory Gardner’s political games are not just wrong but dangerous. Gardner should refuse to vote for a Supreme Court nominee until the people have spoken.”

The ad features a clip of Gardner making a case in March 2016 for letting the next president pick the next justice: “The next president ought to choose the Supreme Court nominee,” the Republican said after Obama nominated Garland. “It’s only fair to the integrity of the Supreme Court.”

Gardner says he will 'vote to confirm' qualified Supreme Court nominee

Aberger said in a statement that Coloradans shouldn’t be surprised Gardner has reversed his position to align with McConnell’s, since Gardner has voted with the Kentucky Republican 92% of the time.

Democrats are seeking to focus the fight against Barrett’s confirmation on the fate of the Affordable Care Act, known as Obamacare, which is targeted by a lawsuit to overturn the health care legislation scheduled to be heard by the Supreme Court a week after the election.

“The next Supreme Court justice will have a pivotal role in upholding the Affordable Care Act and protecting health care for all Coloradans,” Aberger said.

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