Rand Paul's motion to declare the Senate impeachment trial is unconstitutional defeated 55-45 (Romney, Collins, Sasse, Murkowski, Toomey voting to join Ds). However, it's very unlikely any R is going to vote to convict if they've already gone on the record saying its unconstitutional (it would please no one of their constituencies). So this thing is going now where barring anything new being revealed.
The only thing is going to accomplish is set a precedent for later where former presidents will be routinely impeached post hoc once they've lost office, or the House will vote during office as a motion of no confidence.