With the Senate set for a final vote on health care reform Thursday morning at 8 a.m., the forthcoming House and Senate conference moves front stage as the two chambers figure out how to reconcile their differences.

The House bill, which passed by a slim 5-vote margin, contains the public option, which some liberal members have demanded to be included in a final bill. However, Senate Democrats are expected to have no wiggle room, as getting the necessary 60 senators on board for the less progressive Senate bill has taken months. If just one Democrat declines to support the conference report, the bill will die.

So the spotlight is on liberal Democrats and how they will react if the bill that comes out of conference does not include the public option, as well as what the abortion language will look like.

In a statement released yesterday, Congressional Progressive Caucus Co-Chair Raul Grijalva (D-N.M.) was vague on what exactly he and his 82-member group would support. He did not demand the public option be included in the merged House and Senate health care reform bills, but instead ticked off components of the House bill "that must not be dismissed": public option, strong insurance regulatory reform, affordability protection, employer mandate and a tax surcharge for the wealthy.

"I look forward to working with the House and Senate leadership to pass a final bill that will help the most people and create a realistic pathway to future improvements," said Grijalva. "My support for the ongoing reform effort is predicated on the belief that such a bill is within reach and can be passed in the short term. If a bill with these features is pursued, I will be proud to support it."

In an interview with Roll Call, Grijalva did say there would need to be changes to the Senate bill in conference for it to win enough support in the House, whether Sens. Ben Nelson (D-Neb.) and Joe Lieberman (D-Conn.) like it or not. "They've had their way up to this point," Grijalva said. "For either them or the Senate to expect to send their bill as is through the House is going to be very difficult."

For their part, House Speaker Nancy Pelosi and Majority Leader Steny Hoyer have only indicated that they are ready to work with the Senate to merge the two bills.

"We welcome the developments today in the Senate, and we look forward to reviewing the bill the Senate passes," they said in a statement Monday morning. "The Democratic Caucus is committed to middle class affordability, security for our seniors, responsibility to our children, and accountability for the insurance industry. On that basis, we look forward to working with the Obama Administration, the Senate, and our Caucus to reconcile our bills and send final legislation to the President's desk as soon as possible."