Republican former Treasury Secretary Hank Paulson told CNBC on Monday that Democrat Hillary Clinton has the "temperament" to find middle ground on the big issues facing the nation.

Paulson said on "Squawk Box" he cannot support GOP presidential nominee Donald Trump. "I can't sign on to this sort of populism that's rooted in ignorance and fear and prejudice. I find it abhorrent."

"It comes down to character and temperament, the ability to work across the aisle," he said. "I watched Secretary Clinton, when she was a senator, do that. You learn a lot when you're secretary of state. To me, I'd take that experience any day."

Paulson did say he supports House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell. "I've been working hard to elect Republicans in the Senate and the House. I think it's very important we keep our leadership position [on Capitol Hill]."

Paulson, who headed the Treasury during the presidency of George W. Bush and in the thick of the 2008 financial crisis, broke ranks in June, and said he's going to vote for Clinton.

He said divided government is the best way to break the gridlock in Washington and enact the tax and entitlement reform needed to help restore the economy.