RICHMOND, Va. (WVEC) — Former U.S. Senator John Warner, a Republican, is crossing party lines with his latest endorsement.

Warner, 91. announced his support for Democratic Senator Tim Kaine, as Kaine seeks re-election in November.

The five-term Senator has endorsed Democrats in the past, including Hillary Clinton, but never Senator Kaine.

"Tim's unquestioned integrity and moral character are sorely needed in the Senate at this most unusual time in our nation's history," Warner said in his endorsement. "Americans, myself included, are fervently seeking to support the election of public servants with those basic but essential characteristics. For those reasons, Tim has certainly earned my vote and total support in this election."

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According to the Kaine campaign, Warner will be the Kaine's honored guest at Wednesday night's debate against GOP nominee Cory Stewart.