Sen. Joe Manchin III (D-W.Va.), a moderate who is friendly with the White House, on Monday asked his colleagues to consider censuring President Trump as the Senate moves toward votes on impeachment.

“I do believe a bipartisan majority of this body would vote to censure President Trump for his action in this matter. Censure would allow this body to unite across party lines,” Manchin said in a speech on the Senate floor. “His behavior cannot go unchecked by the Senate and censure would allow a bipartisan statement condemning his unacceptable behavior in the strongest terms.”

It is an effort that could put pressure on some Republican senators as they mull whether to reprimand Trump in coming weeks, even if they vote Wednesday to acquit him on the House’s two articles of impeachment — abuse of power and obstruction of Congress.

But Manchin’s proposal will face obstacles as lawmakers in both parties resist the idea and hew to their leadership’s position on how to respond to Trump’s conduct.

Manchin has prepared a censure resolution for fellow senators to review in coming days, which would be a less severe rebuke than removal from office for Trump’s involvement in pressuring Ukraine to investigate a domestic political rival, former vice president Joe Biden.

“What the president did was wrong,” Manchin said in his speech.

The crux of the case against Trump is the allegation that he withheld military aid and a White House meeting to pressure Ukraine to investigate Biden and his son, Hunter. Hunter Biden served on the board of Burisma, a Ukrainian energy company, while his father was vice president.

The resolution was shared with The Washington Post by a person close to Manchin who spoke on the condition of anonymity to talk freely.

The individual said Manchin has been grappling for weeks with how best to respond to Trump’s conduct and the evidence and arguments made by the House Democratic managers during the impeachment trial; eventually he concluded that censuring Trump would be an appropriate course of action, the person said.

It is not yet clear how Manchin will vote on the two articles of impeachment and whether to remove Trump. He said Monday in his remarks that he remains “undecided.”

Manchin said in an interview later Monday that he is unsure whether Republican senators such as Mitt Romney (Utah) and Susan Collins (Maine) will sign on to his legislation, which remains in draft form.

“I don’t know. I really don’t know. I’ve been talking to people for a while,” Manchin said, noting that he is open to discussing the final language of his resolution with colleagues.

When asked whether he believes he will pay a political price with Trump, with whom he has a personal rapport, Manchin said he will wait and see.

“I’ve had a good personal relationship, one on one, with him. But this is wrong, and he’s not getting good input from his people,” Manchin said of the president’s conduct.

He said his fellow Democrats, including Minority Leader Charles E. Schumer (N.Y.), have been “respectful” as he has moved toward his censure position.

Manchin will face challenges as he attempts to rally support for his idea in coming days. Multiple Senate Republican officials and aides, who spoke on the condition of anonymity to describe private discussions, said Monday that they see few senators willing to pursue censure.

Instead, most Senate Republicans have either insisted Trump did nothing wrong and has been the subject of a partisan impeachment quest, or they have argued that while he might have acted inappropriately, voters should render the verdict on the president at the ballot box in November.

Democrats who spoke under the same conditions said that although some of the party’s senators might support a sanction short of impeachment, they are concerned about backing off their belief that Trump’s conduct deserves removal from office. Pursuing censure, some said privately, could undermine the party’s consistent message that Trump’s conduct warrants that.

Asked to gauge the appetite for censure among Republicans, Sen. Mike Braun (R-Ind.) said: “Zero.”

Sen. Marco Rubio (R-Fla.) — who said in a statement Friday that “just because actions meet a standard of impeachment does not mean it is in the best interest of the country to remove a President from office” — said Monday that he was not interested in pursuing censure and prefers to “just move forward.”

“We have an election in nine months, and that’s, in may mind, the appropriate way for people to take into account how they feel about what they think the president did or didn’t do,” he said. “It’s the ultimate accountability.”

Several Democrats also said they were unsold on censure, calling it a punishment well short of what Trump deserves.

“What he did was an impeachable offense — I think it’s absolutely obvious, and giving a slap on the wrist doesn’t do any good,” said Sen. Jon Tester (D-Mont.).

Sen. Brian Schatz (D-Hawaii) suggested that a censure would only allow Republicans to skirt responsibility for protecting Trump, saying, “I’m not bailing them out.”

One Democrat open to the idea was Sen. Richard Blumenthal (Conn.), who said that “some additional action may well be appropriate” but that he would want to speak with colleagues before endorsing it.

The draft of Manchin’s legislation argues that Trump “used the office of the president of the United States to attempt to compel a foreign nation to interfere with domestic political affairs for his own personal benefit” and says Trump “wrongfully enlisted his personal lawyer to investigate a domestic political rival by meddling in formal diplomatic relations in a manner that is inconsistent with our established National Security Strategy.”

It adds that “Trump hindered the thorough investigation of related documents and prohibited Congress and the American people from hearing testimony by first-hand witnesses with direct knowledge of his conduct.”

The three-page resolution concludes by stating that “no one, not even the president, is above the law” and calls for the Senate to “condemn his wrongful conduct in the strongest terms” that recognize “the historic gravity” of the resolution.

During the last presidential impeachment in 1999, Sen. Dianne Feinstein (D-Calif.) played a central role in trying to assemble a bipartisan coalition to censure Bill Clinton for the conduct that led to his impeachment. But a cadre of conservative Republicans, led by then-Sen. Phil Gramm (Tex.), blocked the move, fearing that it would, in effect, excuse Clinton’s conduct and serve as a rebuke of the House Republicans who pursued a grueling impeachment rather than a censure.

Asked Monday whether she would be open to another attempt at censure, Feinstein declined to comment.

Rachael Bade contributed to this report.