MILWAUKEE (CBS 58) -- Representatives from several groups protested outside Senator Ron Johnson's Milwaukee office on Tuesday afternoon.

They are voicing their opposition to the newest Supreme Court nominee Brett Kavanaugh.

Senator Tammy Baldwin has already said she will not support his nomination.

Johnson hasn't said yet how he will vote.

People protesting say Kavanaugh's nomination could have an impact on future legislation.

"A lot of rights will be taken away, not just some but more specific ones, there are so many things that can be taken away like unions, labor rights, all those things he poses a big threat too," said one protester.

Johnson says the confirmation process should be wrapped up before November's midterm elections.

Kavanaugh is President Trump's pick to replace retiring Justice Anthony Kennedy.