WASHINGTON, DC - JANUARY 12:  U.S. President-elect Donald Trump's nominee for the director of the CIA, Rep.Mike Pompeo(R-KS) attends his confirmation hearing before the Senate (Select) Intelligence Committee on January 12, 2017 in Washington, DC. Mr. Pompeo is a former Army officer who graduated first in his class from West Point.  (Photo by Joe Raedle/Getty Images)
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WASHINGTON, DC - JANUARY 12: U.S. President-elect Donald Trump's nominee for the director of the CIA, Rep.Mike Pompeo(R-KS) attends his confirmation hearing before the Senate (Select) Intelligence Committee on January 12, 2017 in Washington, DC. Mr. Pompeo is a former Army officer who graduated first in his class from West Point. (Photo by Joe Raedle/Getty Images)
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WASHINGTON, DC - APRIL 23:  U.S. Sen. Bob Corker (R-TN) (R), chairman of the Senate Foreign Relations Committee, hugs Sen. Chris Coons (D-DE) (2nd R) after a committee meeting April 23, 2018 on Capitol Hill in Washington, DC. The committee has approved to the nomination of CIA Director Mike Pompeo to be the next Secretary of State. Sen. Coons broke a deadlock and voted "present" to avoid keeping the meeting open until Sen. Johnny Isakson (R-GA) can join the meeting from delivering a eulogy out of town.  (Alex Wong/Getty Images)
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WASHINGTON, DC - APRIL 23: U.S. Sen. Bob Corker (R-TN) (R), chairman of the Senate Foreign Relations Committee, hugs Sen. Chris Coons (D-DE) (2nd R) after a committee meeting April 23, 2018 on Capitol Hill in Washington, DC. The committee has approved to the nomination of CIA Director Mike Pompeo to be the next Secretary of State. Sen. Coons broke a deadlock and voted "present" to avoid keeping the meeting open until Sen. Johnny Isakson (R-GA) can join the meeting from delivering a eulogy out of town. (Alex Wong/Getty Images)
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Secretary of state nominee Mike Pompeo now has the support of three Democratic senators, after two lawmakers said Monday they’d back the CIA director to be the nation’s next top diplomat.

Democratic Sen. Joe Manchin tweeted that he will support Pompeo in his confirmation vote, increasing his chances of being confirmed by the chamber.

“After meeting with Mike Pompeo, discussing his foreign policy perspectives, & considering his distinguished time as CIA Director & his exemplary career in public service, I will vote to confirm Mike Pompeo to be our next Secretary of State,” the West Virginia senator tweeted.

Later on Monday, Democratic Sen. Joe Donnelly of Indiana also said he supports the CIA director to be secretary of state.

“When I met with Director Pompeo, we had a productive conversation about the complex security challenges we face, including the dangerous threat posed by North Korea’s nuclear missile program,” he said in the statement. “We need a secretary of state who will give the President an honest assessment on critical issues, including Russia, Syria, and the defeat of ISIS. I believe Director Pompeo is capable of advancing US interests and leading the State Department, and I will support his nomination.”

Both of the senators join North Dakota Sen. Heidi Heitkamp as Democrats who have to publicly announced their support for Pompeo. All three are up for re-election in states President Donald Trump won in 2016.

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On Monday, the Foreign Relations committee is set to vote on Pompeo – where he is expected to not receive a favorable committee vote, though that won’t stop his nomination, according to GOP lawmakers and aides.

Republican Sen. Rand Paul of Kentucky has said he’ll oppose Pompeo’s nomination, meaning Republicans would need at least one Democrat in order to confirm him in the full floor vote. Now with Manchin and Donnelly’s votes joining Heitkamp’s, Pompeo can afford to lose two Republican votes and still be confirmed. GOP Sen. Jeff Flake of Arizona has signaled he has some concerns about Pompeo’s nomination but hasn’t yet said how he’ll vote.

All eyes had been on a handful of moderate Democrats who Republicans are trying to win over, including Manchin, Donnelly, and Sen. Claire McCaskill of Missouri – all of whom are up for re-election this year in states that Trump won by big margins in 2016.

CNN’s Phil Mattingly, Ashley Killough, Jeremy Herb and Ted Barrett contributed to this report.