Democratic Senators negotiating a public insurance option compromise resumed their talks on Tuesday morning, hoping to broker a deal by day’s end.

The group of five liberal and five moderate Democratic Senators have been tasked by Majority Leader Harry Reid (D-Nev.) with designing a compromise to the current public insurance option that can win the support of at least 60 Senators. The $848 billion health care reform package now under consideration calls for a public option with an opt-out for the states.

Also Tuesday, a vote on Sen. Ben Nelson’s (D-Neb.) abortion amendment is expected. Nelson’s proposal, co-sponsored by Sen. Orrin Hatch (R-Utah), would make it explicitly clear that health care subsidies made available under health care reform could not be used to pay for the procedure.

Pro-abortion-rights Senators expect the amendment to fail. But Nelson said his position on the issue — that he will not vote to end debate on the health care reform bill absent the inclusion of his amendment — has not changed. Nelson is also a participant in the public option negotiations, and hedged Tuesday when asked how close the group is to reaching a deal.

“We continue to talk. And as I say there are a variety of different ideas that have been thrown out there, but no finalization of anything,— Nelson said as he headed to the negotiating session. “It seems that the general direction has been away from the public option as it has been.—

Sen. Jay Rockefeller (D-W.Va.), a liberal who is also participating in the talks, was tight-lipped as he headed into the closed-door meeting, which is expected to run until the Democratic weekly caucus luncheon begins. Senators are set to resume their talks later Tuesday afternoon.

Asked if a deal could be reached on Tuesday, Rockefeller said: “I don’t know. I mean, how can anybody answer that question?—

If and when a compromise is reached, the group plans to submit its proposal to the Congressional Budget Office for scoring, Rockefeller said. However, Rockefeller said it is up to Reid to decide whether to wait for the CBO cost-estimate before presenting the plan to the full Democratic Conference.