COLUMBUS, Ohio — Republican U.S. Sen. Rob Portman is facing attacks on the state’s airwaves for the timing of his decision to withdraw his support from GOP presidential nominee Donald Trump.

The incumbent announced his reversal Saturday more than 24 hours after a video featuring Trump making lewd, sexually charged remarks about women was condemned as offensive, inappropriate and sickening by other Republicans.

Democrats and allied groups, which long criticized Portman for supporting Trump despite a series of statements that insulted and mocked various groups of people, had pilloried him throughout the day Saturday. The state Democratic chairman called him “gutless.” The Democratic super political action committee American Bridge characterized his silence as “disqualifying” for national office.

“His continued support of Trump sends the exact wrong message to young boys — that if you’re rich and famous, you can sexually assault women and brag about it later,” said For Ohio’s Future state director Antonia Webb, in one of many critical statements against Portman. “If the senator had any semblance of a backbone, he’d rescind his endorsement of Trump immediately.”

Portman pulled his endorsement late Saturday, saying he had hoped to support Trump out of respect for the millions of people who voted for him.

“While I continue to respect those who still support Donald Trump, I can no longer support him,” he said in a statement.

He said he would be supporting Trump’s vice presidential running mate, Indiana Gov. Mike Pence, instead, though it’s unclear how a vote for someone not on the ballot would be cast. In Ohio, write-in candidates must be preregistered.

Democratic ex-Gov. Ted Strickland, Portman’s fall challenger, released a new ad Monday saying history will judge Portman a coward. The spots liken the moral calculation on whether to back Trump to those made around Sen. Joe McCarthy, the anti-communist crusader, or George Wallace, the segregationist Alabama governor.

“Portman stood by Trump, even after seeing Trump brag about sexual assault,” the spot said. “Then Portman panicked and scrambled to save himself. History will judge Rob Portman a coward. What will we do?”

Meanwhile, the liberal group targeted a similar message at conservative Christian women, noting the crudity of the video and urging them to defeat Trump and Portman and vote for Strickland and Democratic presidential nominee Hillary Clinton.

Clinton was in Ohio on Monday for a rally, where Strickland planned to distribute fliers saying “20 Times Rob Portman Declined to Drop Trump.”

Asked to respond to the ads, Portman’s campaign stuck to its criticisms of Strickland.

“As governor, Ted Strickland nearly ruined Ohio when the state lost 350,000 jobs and ranked 48th in job creation, and now Ted Strickland’s shameful behavior is ruining whatever was left of his reputation,” campaign manager Corry Bliss said. “Ted Strickland is running the worst campaign in America and is fast becoming a national laughingstock. I hope he enjoys what we have in store for the final four weeks of his retirement tour.”

Portman, who has been well ahead of Strickland in fundraising and polls, released a new ad Monday unrelated to Trump.