None of them are up for re-election in 2018. Collins and Capito are up in 2020. Murkowski and Portman in 2022. It will have blown over long before then.
That explains there liberal vote. closer to re-election their views will change.
Our best chance for 2018 is to replace at least 3 (preferably more) Democrat Senators with Conservative Senators who will vow to vote to repeal Obamanation.
The four RINO Senators who vote no should definitely be targeted in 2020 and 2022. IMHO, any Republican Senators who vote to ratify President Trump's nominees and to repeal Obamanation should not be targeted.