Senate Republicans, in an apparent bid to hurry the impeachment process along, reportedly are leaning against calling any witnesses in their rush to acquit President Trump of wrongdoing.

House Democrats unveiled two articles of impeachment Tuesday: abuse of power and obstruction of Congress, neither of which are statutory crimes. The House Judiciary Committee spent Wednesday marking up the measures and the full House could vote on the articles next week before Congress adjourns for the holidays.

Sen. Ron Johnson, R-Wis., told Bloomberg Wednesday a growing number of GOP senators simply want to hear Democrats make their case and a rebuttal by Trump’s team before moving to an immediate vote to keep the process from getting “messy.”

White House press secretary Stephanie Grisham told Fox News on Tuesday the White House would like to see “a lot of witnesses,” but Sen John Cornyn, R-Texas, said if the votes are there, the chamber should just move forward.

Senate Majority Leader Mitch McConnell, R-Ky., has said he plans to hold up other business until impeachment has been dealt with. Sixty-seven senators would have to vote in favor of impeachment to remove Trump from office, and hitting that threshold is unlikely, especially if no additional evidence is presented. Republicans hold the majority in the Senate, 53-47.

Earlier, Sen. Lindsey Graham, R-S.C., chairman of the Senate Judiciary Committee, indicated Republicans planned to muddy the case by calling former Vice President Joe Biden’s son, Hunter, as a witness to testify about his relationship with the Ukrainian energy company Burisma, and also by investigating a debunked conspiracy theory positing that Ukraine, not Russia, interfered in the 2016 U.S. presidential election. He also planned to call House Intelligence Committee Chairman Adam Schiff, D-Calif., who headed the impeachment inquiry and the whistleblower whose complaint touched off the investigation.

The articles of impeachment stem from Trump’s July 25 phone call with Ukraine President Volodymyr Zelensky during which he pressed Zelensky to investigate Biden, his son, Burisma and the conspiracy theory. At the time, he was holding up $391 million in military aid to the former Soviet republic, which is fighting Russia-backed separatists in its eastern provinces.

Senate Minority Leader Chuck Schumer, D-N.Y., urged his Republican colleagues to keep open minds, calling the allegations against Trump serious and urging them to do “our sworn duty to uphold and defend the Constitution.”

Trump has said he wants a Senate trial, taunting Democrats to adopt the articles of impeachment quickly and teasing that he might consider testifying.