Leading House Democrats said Thursday they will negotiate compromise children’s health insurance legislation informally with their Senate counterparts if Senate Republicans continue to block a formal conference committee on the bill.

House Democrats held a rally with labor union activists intended to pressure both President Bush and the Senate to act quickly on a renewal of the State Children’s Health Insurance Program, or SCHIP, which covers more than 6 million low-income children.

Both chambers have passed bills to renew the program, which expires Sept. 30. But Senate Republicans have blocked the appointment of senators to a conference committee that would negotiate a final bill, saying they want an agreement to limit the bill’s scope and expense before a conference convenes.

The House bill (HR 3162) is broader and more expensive than the Senate version (HR 976).

One alternative to a conference is a short-term extension of SCHIP, perhaps to Nov. 15, Rep. Pete Stark, D-Calif., chairman of the Ways and Means Health Subcommittee, said.

The Senate version is much more bipartisan than the House bill; it passed 68-31 on Aug. 2, enough to override a veto. The House bill passed 225-204 on Aug. 1, far short of the two-thirds necessary to overcome a veto.

But each bill has provisions that are objectionable to many members in the opposite chamber.