Senate Democratic leaders cautioned their rank and file Thursday to keep their powder dry on a variety of issues related to their health care reform drive as House and Senate negotiators continue to talk about how to ensure final passage of an overhaul this spring.

Sen. Bob Casey (D-Pa.) said Senators attending a caucus meeting on health care were asked to refrain from making judgments on whether to add student loan provisions to a reconciliation package as well as on the overall bill, in order to avoid disrupting the high-pressure talks between the House and Senate.

“If the big question is what will the House do, why would we go out and start having people draw lines in the sand?” Casey asked. “That was one of the points [leadership made]. The main thing that leadership wanted to do is just give us a sense of the state of play, where things are, knowing that a lot of it would be unresolved but it’s better than just … coming to everyone saying, ‘Everything’s cooked. It’s done. The cake is here; everybody eat it.'”

Majority Whip Dick Durbin (D-Ill.) said Senators were given a general description of the elements being considered for the reconciliation bill, most of which are contained in President Barack Obama’s $950 billion proposal. Following that, Health, Education, Labor and Pensions Chairman Tom Harkin (D-Iowa) and Budget Chairman Kent Conrad (D-N.D.) presented arguments for and against eliminating subsidies to banks that offer student loans as part of the reconciliation package.

Though Conrad has been publicly critical of the student loan element, Durbin said he outlined both the positives and the negatives of making it part of the plan.”He made a case for including it — what he thought was the strongest case — and of course went back to a position shared by some that it does add more weight to be lifted,” Durbin said. “I frankly think it gives us more buoyancy. It really helps us because some of the things accomplished here are really going to help a lot of people across America.”

Harkin earlier Thursday held a press conference with House Education and Labor Chairman George Miller (D-Calif.) to press for inclusion of the student loan package.

Miller said the proposal would help House Democratic leaders corral the necessary votes to pass both the Senate health care measure and the reconciliation bill designed to address House concerns with the Senate bill. Miller said it would be particularly helpful in securing the votes of the Congressional Hispanic Caucus and the Congressional Black Caucus.

Durbin and Casey said it appears more Democratic Senators favor adding the student loan piece, but that no decision had been made.

Meanwhile, House and Senate leaders continue to trade proposals and costs estimates with the Congressional Budget Office as they try to craft a reconciliation package that reduces the deficit and puts the total cost of a health care overhaul at less than $1 trillion. Leaders first sent Obama’s proposal to be scored as a starting point, but Durbin acknowledged they are considering adding and subtracting to that package.

“There’s still smaller substantive issues that are being decided,” Durbin said.