The Senate faces an uncertain timeline on a target date for passing legislation to repeal and replace Obamacare after the House narrowly voted for the American Health Care Act last week, The Hill reported on Monday.
Senate Majority Whip John Cornyn refused to say when he hoped to be ready for a vote on the issue.
"There is no timeline; When we get 51 senators, we'll vote," Cornyn said, The Hill reports.
With no Democrats expected to support the bill, the GOP, with 52 seats in the upper chamber, can afford only two defections, which would allow Vice President Mike Pence to break a 50-50 tie.
Republican Sen. Susan Collins reiterated to ABC's "This Week" that the Senate will take its time considering the bill, because the upper chamber will be "starting from scratch" on healthcare legislation.
Republican Sens. Dean Heller and Rob Portman have already issued statements after the House passed the bill, that they did not support it, according to The Hill.
Among the concerns of some GOP senators is that the House bill would negatively impact Medicaid recipients in states that expanded the program under Obamacare, and increase premiums on both older and poorer Americans.
The Boston Herald reports that AARP has already launched an ad campaign warning that those with pre-existing conditions could face premium hikes of up to $25,000 a year under the bill passed by the House and "while millions of older Americans get priced out of coverage, big drug and insurance companies get billions in tax breaks."
The difficulty for the GOP is that if it does make changes in the bill to appeal to moderate Republican senators who disagree with aspects of the legislation, it could lose the support of more conservative members.
Sen. Rand Paul, for example, said "the Freedom Caucus were given some good things but will any of them stay?" according to The Hill. "If all the good stuff is lost and we're left with just a subsidy bill . . . I'm not real excited about that."