As Democrats look to resolve bicameral differences over health care reform, House Democratic leaders are attempting to ensure that any action they take to approve the Senate’s original $871 billion package will be reciprocated across the Dome by passage of companion reconciliation legislation.

Senate Democrats already appear to have rejected one idea in which they would sign a letter promising to vote for the reconciliation bill. But another option, this one using the legislative process in the House to tie the underlying Senate health care reform bill to the reconciliation package of adjustments being sought by House Democrats, is still on the table, sources say.

“House Democrats are trying to draft a creative rule to bring up the Senate bill, but only send it to the president if the Senate makes certain changes in reconciliation,” said one downtown operative who has monitored the health care debate for the past year.

The most likely scenario for getting a final health care bill to President Barack Obama’s desk calls for the House to clear the health care bill approved by the Senate on Christmas Eve, as well as a sidecar package of adjustments. The Senate would then clear the sidecar under reconciliation rules, enabling them to sidestep a Republican filibuster.

House Democrats, nervous that Senate Democrats might fail to pass the reconciliation bill, are searching for ways to ensure that the Senate bill does not become law unless some key changes and adjustments are made.

Congressional Democrats in January had been on the verge of agreeing to a reconciled package of the House and Senate health care bills, which passed late last year, but those plans were derailed by the election of Sen. Scott Brown (R-Mass.), who enabled the GOP to sustain a filibuster of health care.

Under the Senate’s reconciliation rules, only 51 votes are needed to clear a bill, rather than the customary 60.