“Once the House votes to impeach, everything then shifts to the Senate.”
That sounds like the answer. Once the house has a vote it is out of their hands.
So I guess the question is will the Republicans hold it up? I’m sure quite a few of them have self interest at heart more than the country.
Post 1132.
One other thing. The Senate has the right to dismiss the charges of impeachment by a majority vote and refuse to hold a trial. However, this has never happened in the past.