Republican senators battled behind closed doors Tuesday over a proposal to beef up Social Security benefits for people who are eligible for non- Social Security government pensions.

The legislation, which has passed the House, is expected to reach the Senate floor Wednesday, but some Republicans who are worried about its price tag are hoping to stop it dead.

One GOP senator who attended Tuesday’s meeting described it as “an intense discussion.”

“I think most of our members were alarmed that something so big” would come straight to the Senate floor, the senator said, noting the legislation had not been marked up by the Senate Finance Committee.

A group of Senate conservatives led by Sen. Rand Paul (R-Ky.) are demanding Social Security reforms, such as gradually raising the retirement age, to offset the cost of repealing two policies that reduce Social Security benefits for public-sector workers.