WASHINGTON – A Republican group that has pressed GOP lawmakers to denounce President Donald Trump over his actions in Ukraine ramped up its campaign Wednesday by targeting two Texans as the impeachment vote nears.

Republicans for the Rule of Law announced digital billboards in Amarillo, aimed at Rep. Mac Thornberry, and in Brenham, aimed at Rep. Michael McCaul.

The billboards ask why the White House has blocked testimony from key witnesses in the impeachment inquiry, dramatizing the message by depicting four top Trump aides with duct tape over their mouths: Acting Chief of Staff Mick Mulvaney, former National Security Adviser John Bolton, Secretary of State Mike Pompeo, and Rudy Giuliani, Trump’s personal lawyer and a key figure in the Ukraine scandal.

“What is Trump hiding? Rep. McCaul, we need the whole truth,” it reads.

For weeks, the group has aired ads on Morning Joe and Fox & Friends in the districts of some House Republicans in competitive districts.

This week, the ad will also air on Fox & Friends in the McCaul and Thornberry districts, the group said.

Trump doesn't want the people who know the most to testify. Why not? What's he afraid of?

This new ad from Republicans for the Rule of Law will air in key states and districts on TV and will be promoted digitally. pic.twitter.com/XeOOUS6xKo — Bill Kristol (@BillKristol) November 27, 2019

“The president doesn’t own the government, and he’s not above the law,” said Chris Truax, spokesman for the group. “President Trump has been given every opportunity to answer the charges against him. He demands friendly witnesses, yet refuses to allow his most loyal supporters to testify. He complains the proceedings are unfair, yet refuses to allow his lawyers to participate in the hearings. If President Trump really could prove he is innocent of the impeachment charges against him, he would have made some effort to do so by now.”

The choice of targets in Texas isn’t entirely clear.

Thornberry, former chairman of the Armed Services Committee, is one of a half-dozen Texas Republicans who are retiring rather than seek reelection next year. In that sense he’s free to vote his conscience, but while he has criticized Trump’s tactics in Ukraine, he has not signaled any willingness to impeach. But the district is one of the most solidly Republican in the country.

McCaul, whom Trump had eyed for a Cabinet post at various points, has been outspoken in criticizing the Democrats’ drive for impeachment. He denounced the inquiry as “one-sided” and a “sham.” And he has embraced the claim that Intelligence Committee Chairman Adam Schiff, D-Calif., knows far more about the whistleblower whose complaint triggered the investigation than he’s admitted.

His district, which runs from his hometown of Austin to suburban Houston, is more of a battleground. Democrats have targeted him in 2020.