WASHINGTON (Reuters) - The White House cranked up pressure on Wednesday on Democratic senators facing tough re-election fights to back secretary of state nominee Mike Pompeo, who looked increasingly likely to face a rare committee rejection before the full Senate can vote on his nomination.

President Donald Trump confirmed the CIA director is already deeply involved in diplomacy via a meeting with North Korean Leader Kim Jong Un. But even if he is confirmed, Pompeo risked becoming the first secretary of state known to take office without the approval of the Senate Foreign Relations Committee.

Pompeo needs Democratic votes to gain approval from the panel where one Republican, Senator Rand Paul, has pledged to oppose him. Paul was the only one of Trump’s fellow Republicans to vote against Pompeo’s nomination to be CIA director.

The committee includes 11 Republicans and 10 Democrats. Nine of the 10 Democrats have announced they oppose Pompeo. The 10th, Senator Chris Coons, is undecided.

Like many Democrats, Paul said Pompeo is too hawkish to be the country’s top diplomat. He also criticized him for supporting the CIA’s past use of waterboarding and other interrogation techniques widely considered torture.

Pompeo can be approved by the full Senate even without the committee’s backing, and supporters say he is likely to win at best a slim majority in the 100-member chamber.

But no secretary of state is ever known to have been rejected by the committee. Before the 1920s, such votes were not made public, and none has been rejected by the panel since.

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‘CONSEQUENCES’

On a White House call with reporters, Republican Senator Tom Cotton warned Democratic senators up for re-election in states Trump won in 2016 not to vote against Pompeo. He mentioned Joe Donnelly of Indiana, Heidi Heitkamp of North Dakota and Joe Manchin of West Virginia.

“If they do so - and they’re up for re-election - they may suffer the consequences,” said Cotton, an outspoken Trump supporter who blasted the Foreign Relations Committee as out of step with the rest of the Senate.

A Manchin aide declined comment, a Heitkamp aide said she had not made a decision on Pompeo, and Donnelly’s office did not respond to a request for comment.

Senator Robert Menendez, top Democrat on Foreign Relations, announced earlier on Wednesday he would cast a “no” vote.

Menendez criticized Pompeo for failing to disclose his recent trip to North Korea in meetings with lawmakers. He said Pompeo also was not forthcoming when questioned about the investigation into whether the Trump campaign colluded with Russia to sway the 2016 election.

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“I believe our nation’s top diplomat must be forthright,”

Menendez said in a speech at the Center for Strategic and International Studies think tank.

In Florida, Trump told reporters before a lunch with Japanese Prime Minister Shinzo Abe that he expected Paul would change his mind. “He’s never let me down. And I don’t think he’ll let us down again,” Trump said.

“I think Mike Pompeo is going to go down as one of the great secretary of states,” Trump said. Pompeo and Kim had a “great meeting,” Trump said, adding, “He’s very smart but he gets along with people.”

Sergio Gor, Paul’s deputy chief of staff, said the senator had agreed to meet with Pompeo but nothing else had changed.

Democratic opponents also say Pompeo’s opposition to gay marriage and past ties to anti-Muslim organizations make him too ideologically conservative to represent the country on the world stage.

Republicans who back Pompeo accuse Democrats of playing politics at time when the country needs a secretary of state to deal with such crises as North Korea and Syria.