Republicans in the Senate are struggling to come up with the five votes they'd need to ensure passage on Wednesday of a House bill raising the debt ceiling.
The measure is likely to win support from the upper chamber's 53 Democrats and the two Independents that caucus with Democrats.
But only one Republican, Sen. Mark Kirk (Ill.), has so far said he would back the bill.
The measure needs 60 votes because Sen. Ted Cruz (R-Texas) is filibustering the bill over the lack of spending reforms attached to it.
Kirk told The Hill the vote would be close.
“I think it’s narrow," he said.
Sen. Susan Collins (R-Maine) is expected to vote yes but told The Hill she was not prepared to announce her position on Wednesday morning.
A number of other GOP centrists said Wednesday they plan to vote against cutting off debate for the bill.
Retiring Sen. Saxby Chambliss (R-Ga.) and Sen. Richard Burr (R-N.C.), two friends of Speaker John Boehner (R-Ohio), said they are voting “no.”
Chambliss said he was unsure if the legislation would receive 60 votes.
Nonetheless, he said he did not begrudge Boehner for bringing a clean bill to the House floor, given the inability of House Republicans to coalesce around an alternative plan.
“John made it very plain early on that he was going to make sure the debt ceiling got raised and we’d pay our bills,” he said. “He’s been there for months.”
“I think the vote to raise the debt ceiling should be used to address the underlying problems, so I will be voting no,” she said.
“I think we should have had concessions made to reduce the debt,” McCain said.
On the Democratic side, the most vulnerable senator said Wednesday he would vote to increase the $17.2 trillion debt ceiling.
“I have been consistent in making sure we don’t default on the bills that we owe,” he said.
Only 28 House Republicans backed the debt ceiling bill in the House, where it was approved in a narrow 221-201 vote. Only two Democrats voted against it.
The bill extends borrowing authority through March 15, 2015, essentially removing the threat of any fiscal crisis ahead of the 2014 midterm elections.
— Bernie Becker contributed.