President Donald Trump is expected to announce his nominee to fill the vacant Supreme Court seat on Tuesday, and Senate Democrats have already vowed to filibuster the pick, no matter who it is.

Leonard Leo, Supreme Court advisor to Trump, thinks it would be a big mistake for Democrats to oppose the president's choice.

He pointed out that Democrats have a lot of seats up in 2018, including ten in red states where Trump won big in the 2016 election, so they have to think very carefully about what ground they stake out in the coming months.

"Sen. Schumer and others started right after the election saying they were going to oppose anybody," Leo said. "And now, they're starting to walk those comments back by saying they want someone who's mainstream and who might get some bipartisan support, like Roberts and Alito."

"I think they're playing their cards close to their vest, because they're not really sure how some of the Senate Democrats who are in vulnerable states might react to an all-out filibuster."

Watch more above, and let us know what you think in the comments.

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