West Virginia’s lone Democratic senator, Joe Manchin, who now faces a tough re-election fight in 2018 without the aid of a Democratic governor in his state said on Thursday that he was “disappointed” by the news, but indicated that he would still be willing to work with the governor.

“While I do not agree with his decision, I have always said that I will work with anyone, no matter their political affiliation, to do what is best for the people of West Virginia,” the senator said in a statement. A spokesman for Manchin confirmed that the senator is not switching parties or leaving his West Virginia Senate seat.

Manchin is up for reelection in 2018 and faces a primary challenge on the left from a progressive candidate running on a Bernie Sanders-style platform. The West Virginia senator also faces Republican challengers Evan Jenkins, a Republican representative who was once a Democrat himself, but switched parties in 2013, and Patrick Morrisey, West Virginia’s Republican attorney general. Manchin endorsed Justice during his run for governor.

The Democratic Governors Association put out a scathingly critical statement in response to Justice’s announcement Thursday evening, accusing Justice of “deceiving the voters of West Virginia when he ran as a Democrat 8 months ago.”

This won’t be Justice’s first time switching parties. In May 2015, The Wall Street Journal reported that Justice switched affiliation from Republican to Democrat in February of that year, citing state records. The news that Justice would switch parties was reported earlier in the day by The New York Times.

It’s not immediately clear why Justice opted to switch parties. In their statement, the Democratic Governors Association suggested the move was purely out of self-interest, with a possible financial motive.

“As Republicans have repeatedly said, Jim Justice owes millions of dollars in unpaid company taxes, after a deal with a Russian coal company. The debts have only worsened during Justice’s term term as governor,” DGA executive director Elisabeth Pearson said in a statement. “If President Trump cut a deal, we hope it does not put U.S. taxpayers on the hook to bail out Jim Justice’s personal finances.”

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