Moderate Sen. Ben Nelson (D-Neb.) confirmed Thursday that he is dissatisfied with compromise abortion language designed to secure his support for the health care reform bill.

However, in an interview with KLIN radio in Nebraska, Nelson said there are additional “substantive— problems with the bill beyond restrictions on abortion funding. Nelson mentioned the legislation’s proposed expansion of Medicaid, a program jointly funded by the states, as one of his chief objections.

“That’s not enough,— Nelson said, when asked if resolution of the abortion issue would be enough for him to vote to end debate on the bill. “The problem with the legislation is, it is complex, and it’s further complicated by tax increases as a means of extending coverage to people who don’t have it. There is no free ride here.—

“If there isn’t a way to raise money in tight times, this needs to be scaled back,— Nelson continued. “I’ve said this needs to be handled on an incremental basis. … A deadline and a timeline that is out there that is not achievable isn’t helpful. I couldn’t tell you that they couldn’t come up with something that would be satisfactory on abortion between now and then, and solve all the other issues that I’ve raised to them. But I don’t see how.—

Nelson has made clear since the outset of the debate that he would not support Majority Leader Harry Reid’s (D-Nev.) health care package absent strong restrictions on federal funding for abortions. The compromise language was negotiated by Sen. Bob Casey (D-Pa.), who also opposes abortion rights.

“The compromise adds important new initiatives addressing teen pregnancy and tax credits to help with adoptions,— Nelson said. “These are valuable improvements that will make a positive difference and promote life. But as it is, without modifications, the language concerning abortion is not sufficient.—

Meanwhile, Nelson is coming under increasing pressure at home to vote against the package. Gov. Dave Heineman (R) argued that Nebraska cannot afford to pay for the Medicare expansion called for as a part of the bill. Sen. Mike Johanns (R-Neb.) and Nebraska’s all-Republican House delegation also oppose the Democrats’ health care reform bill.

Casey told reporters Thursday that he continues to work on a potential abortion compromise, but he acknowledged he was feeling political heat over his role. Casey noted that anti-abortion-rights groups were airing ads critical of him in at least two media markets in Pennsylvania.

“I’m not going to react to what groups are saying because we’re not there yet,— Casey said. “I think it would be more appropriate when there’s something that is in front of everyone and then we can have a debate about whether it’s adequate or whether it works or not.—

Still, Casey appeared cautiously optimistic that he and Nelson could come to an accord that would not alienate Senate liberals.

“I called Nelson today and we got on the phone and we talked. If he didn’t want to talk I’m sure he would have figured out a way not to,— said Casey. He added, “I think there are some things that we can talk about beyond what we’ve talked about heretofore.—

Casey said the challenge he faces is making sure federal health insurance subsidies would not go to pay for abortion coverage that many private insurers offer as part of their plans. He said that task has been complicated by the fact that there is not a legislative model for restricting such funding, given the bill would create both the subsidies and a government-run insurance market exchange.

When asked if he believes the fate of the bill hinges on his ability to negotiate a compromise, Casey joked, “Don’t put that on me. Can’t I get some help?—

Emily Pierce contributed to this report.