The continuing resolution that will come out of the Senate will almost certainly be a larger and more complicated measure than the stopgap funding measure the House coped with this week.

How far Democrats in the Senate hope to take the bill remains an open question, however, with lawmakers trying to balance concerns over the effects of the sequester on federal agencies and spending on major regulatory initiatives with the fundamental need to fund the government through the rest of the fiscal year.

Conservatives in both chambers appear willing to include more appropriations bills in the Senate version of the fiscal 2013 spending package, as long as the $85 billion slice to the federal budget under the sequester is preserved. The fiscal 2013 measure (HR 933) that went through the House on Wednesday combines Defense and Military Construction-Veterans Affairs bills with a stopgap CR for the rest of federal agencies, giving the military-related programs some ability to soften the blunt impact of the sequester.

The House’s bill effectively would cap fiscal 2013 spending at about $984 billion, a roughly $59 billion cut from the previous budget year’s spending, effectively entrenching the sequester for the current fiscal year.

Rep. Mick Mulvaney, R-S.C., said he doesn’t object to adding other spending bills as long as the total cost of the package stays the same. “I’m more interested in the top-line number,” Mulvaney said.

The challenge in the days ahead will be to devise a Senate package that can do more than win the needed GOP support for passage. To advance, the measure also would need to be written in a way that doesn’t spark a Republican backlash. That makes some of the more controversial bills, such as the Financial Services and Labor-Health and Human Services-Education measures, less likely to be included in a continuing resolution that will pick up after the current stopgap funding plan expires March 27.

“It depends on the structure of it, but the important thing is the overall cap,” said Sen. Jeff Flake of Arizona, a conservative freshman Republican with a long track record in the House of opposing spending measures.

Tom Cole of Oklahoma, a House GOP appropriator, endorsed this approach. “That’s fine,” Cole said. “We will negotiate it out, we’ll avoid a government shutdown.”

With the public blessing of Senate Majority Leader Harry Reid, D-Nev., Senate Appropriations Chairwoman Barbara A. Mikulski, D-Md., has been trying to craft a package that would contain more spending bills than the two contained in the House bill.

Sen. Richard C. Shelby of Alabama, the ranking member on the Appropriations Committee, said he was in conversations with Mikulski and was optimistic that other provisions could be added in the Senate. “We’ve got to see what’s doable,” he said. “I don’t think it will be an omnibus. I don’t think so. But it might be some kind of a hybrid. I’d call it a hybrid, smaller than a minibus.”

New spending bills added to Mikulski’s measure may still reflect the cuts made by the sequester, but they would move money around within the cap to allow agencies to better manage these reductions. Leaving an agency running under a CR means it will be cutting spending while still following budget marching orders that Congress set in late 2011 when it cleared the fiscal 2012 appropriations laws (PL 112-55, PL 112-74).

Among the clear candidates for the Senate’s fiscal 2013 bill are those from the Commerce-Justice-Science subcommittee and the Agriculture and Homeland Security measures. Staff members and appropriators largely worked out House-Senate compromise agreements for these two last years. Sen. Susan Collins of Maine, the ranking Republican on the Transportation-Housing and Urban Development Appropriations Subcommittee, said she hoped her panel’s bill could be added to the package but that an obstacle remained.

“I just don’t know if we are going to be able to resolve all of the issues with high-speed rail,” Collins said.

The differences over numerous such issues present serious hurdles to efforts to expand the scope of the funding resolution, and questions over the funding for issues with sharp partisan division, such as implementation of the Affordable Care Act and new financial regulations, provide even steeper barriers.

“I don’t think we would want any game-breakers,” said Sen. Dan Coats of Indiana, the ranking Republican on the Homeland Security Appropriations Subcommittee.

Among the bills facing such a challenge are the Financial Services measure, which would cause a fight about funding the 2010 Dodd-Frank overhaul (PL 111-203) of the financial services industry, and the Labor-Health and Human Services-Education measure, which would spark debate about money to be spent on the 2010 health care overhaul (PL 111-148, PL 111-152). The Interior-Environment measure also has been marked by some deeply partisan splits.

Other bills may be excluded from Mikulski’s measure because they contain unresolved issues, said Sen. Lamar Alexander of Tennessee, the ranking Republican on the Energy-Water Appropriations Subcommittee. With 13 or 14 items still to be worked out on his panel’s bill, he said, it’s “not at the head of the line.”