Republican leadership is close to not having the votes to advance a Senate healthcare reform bill despite adding more money and making changes in an effort to lure more support.

Sen. Susan Collins, R-Maine, said the bill still has too many deep cuts to Medicaid to get her support for a procedural motion to advance the bill expected early next week. Sen. Rand Paul, R-Ky., said the bill won't get his support because it doesn't fully repeal Obamacare.

In addition, key centrist Rob Portman, R-Ohio, said he was undecided on the procedural motion to advance the bill. But Portman indicated he is still looking at the bill and wants to know the score on insurance coverage and deficit spending from the Congressional Budget Office.

Sen. John Thune, R-S.D., a member of Senate Republican leadership, said leadership hopes to bring up the bill for a motion to proceed early next week.

The GOP can afford only two Republican defections out of its 52-seat majority since Vice President Mike Pence can break any 50-50 tie.

A score from the CBO is due early next week.

Several other Republican holdouts are joining Portman in considering whether to vote for a motion to proceed.

Sen. Shelley Moore Capito, R-W.Va., said she is still undecided on a motion, as is Sen. John Hoeven, R-N.D.

"I am reserving judgment," Hoeven said. "I've got a little reading to do here and I want to see some CBO scores."

Several senators leaving a closed-door briefing on the new bill said it is still likely to change due to amendments.

"We've got room to make additional changes," said Sen. Mike Rounds, R-S.D. " There shouldn't be consensus yet. If that were the case we would vote today. But are we getting there? I think we are."

The GOP leadership was able to get some initial holdouts on board with the new version of the bill. Sen. Ted Cruz, R-Texas, said that he would vote for the bill after leadership included a version of his amendment to allow insurers to sell plans that don't comply with Obamacare regulations.

But it is not clear if conservative Sen. Mike Lee, R-Utah, is also on board. He previously has said that he wouldn't support the bill without the amendment as previously written but hasn't decided whether the newly revised proposal is enough to get him to yes.