Some key U.S. senators still had concerns about the Republican tax bill in the Senate, as a procedural motion to formally open debate on the measure was approved on Wednesday.
Here is a list of Republicans pivotal to the bill's fate.
Susan Collins
The moderate senator from Maine has qualms about Republicans’ plan to include in the tax bill a repeal of a federal fee imposed on people who do not comply with Obamacare's "individual mandate."
The fee is meant to encourage young, healthy people to get health insurance so that premiums are affordable for old, sick people. Collins and others fear repealing the fine would drive up insurance premium costs, canceling out tax-cut gains that many of their constituents might get from the tax bill.
Collins said Republican leaders had promised her to take up two healthcare provisions before the end of the year to help mitigate the impact of repealing the fee. Those provisions would help insurers cover expensive patients and continue Obamacare subsidy payments for low-income people for two years.
Collins has also prepared an amendment to the tax bill to make state and local property tax deductible up to $10,000, a provision that is part of the House of Representatives' tax bill. Both the Senate and House bills end deductibility of state and local tax income and sales tax. Unlike the House bill, the Senate bill ends property tax deductibility too.
Collins sidestepped a question on whether she would vote for the tax bill. She said: "We're doing this one step at a time."
Lisa Murkowski
The senator from Alaska will vote for the tax bill, she wrote on Twitter on Wednesday evening.