Sen. Lisa Murkowski of Alaska, the only Republican who has endorsed the proposal, expressed uncertainty Monday when she was asked to describe the path to 60 votes in the evenly split chamber. "I don't know. I don't know. It's a challenging one. I think we just have to be honest with it," Murkowski said. "You've got to find an awful lot of Republicans to join us on this."... Sen. John Cornyn of Texas, the former chief vote counter for the Republican caucus, said he opposes the measure and intends to talk to his colleagues "so they understand what the implications are." "It is basically doing through the back door what Democrats are trying to do through the front door on S.1 and H.R.1," he said, using the congressional names for the bills. "What I don't want to happen is if S.1 doesn't make it because people like Sen. Manchin are opposed to it that people say, 'Well, this is kind of a lesser included provision.' It's just as big of a problem as S.1."