President Trump’s eldest son warned Republicans that they better vote in the November midterm elections or Democrats could move to impeach Supreme Court nominee Brett Kavanaugh if they regain control of Congress.

Kavanaugh has not yet been confirmed to the Supreme Court, though it’s likely he will be this weekend, but some Democrats have already floated the possibility of impeachment.

“Trump supporters — The fight isn’t over. You better believe that Democrats are going to do everything in their power to impeach Kavanaugh from the Supreme Court if they take control of Congress in November,” Trump Jr. tweeted Friday.

“This is war,” he continued. “Time to fight.”

Democrats need to gain 23 seats in the midterm elections to win back the House, which can bring articles of impeachment against a justice. Democrats face longer odds at a “blue wave” in the Senate, which would hold a trial for the alleged misconduct. A conviction would require at least 67 votes in the Senate to remove an individual from office.

Reps. Ted Lieu, D-Calif., and Luis Gutierrez, D-Ill., have both said impeachment is possible if Democrats retake the majority.