(CNN) Democratic Sen. Heidi Heitkamp of North Dakota on Thursday announced her support for Mike Pompeo's nomination for secretary of state, becoming the first Democrat to say she'll vote for the current CIA director to be the nation's top diplomat and giving him a much-needed vote for his confirmation.

"Pompeo demonstrated during this nomination process and during our meeting in March that he is committed to empowering the diplomats at the State Department so they can do their jobs in advancing American interests," Heitkamp said in a statement.

While Republicans have long felt Pompeo would be approved in the end, his confirmation was in question after Republican Sen. Rand Paul of Kentucky announced he would oppose it and as Republican Sen. John McCain remains in Arizona battling cancer -- two factors that complicate the Senate vote math for Pompeo.

While he's not yet received a committee vote, Pompeo is expected to need at least one Democrat to vote with Republicans. While Heitkamp's support represents a good sign for Pompeo, it's still unclear whether Republicans will need more Democrats to get his nomination across the finish line, as Republican Sen. Jeff Flake of Arizona is still undecided.

Heitkamp is one of a handful of Democrats that Republicans have been targeting as possible "yes" votes for Pompeo, given her status as a red-state Democrats up for re-election this year.

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