With an eye toward the legislative calendar, House GOP leaders are considering bundling must-pass spending bills to accelerate the lengthy process of debating them on the floor.

In doing so, however, they risk angering conservatives, who note that leadership has long promised an open process so they can offer hundreds of amendments aimed at cutting spending that they can tout on the campaign trail.

All of this underscores the quandary Appropriations Chairman Hal Rogers faces in trying to pass his dozen bills before the House adjourns this presidential election year: Short workweeks and pushback from Members of both parties will make it a difficult task to complete.

“Whatever we do, I want these bills on the floor under an open rule so Members can offer amendments as they see fit,” the Kentucky Republican said. “But mainly, I want to get the 12 bills considered. And floor time is at a real premium this election year, so we’re trying to expedite those as best we know how.”

Though the House recesses every third week and each workweek contains three or four workdays, an aide to Majority Leader Eric Cantor (R-Va.) said appropriators need not worry about scheduling.

“We will continue to work with the Appropriations Committee regarding scheduling to ensure adequate floor time,” the aide said.

Nevertheless, this week marks the first floor debate on an appropriations bill — the Commerce, Justice and science bill — which will test how long it takes to work through amendments and pass a bill, or whether it can pass at all.

“It really depends on the Members and the amendments. If they come out with a couple hundred amendments, it’s going to be tough,” said Rep. Steven LaTourette (R-Ohio), an appropriator.

Already, Members will be debating well into the night, and if the process drags on, leaders could consider packaging some combination of bills dealing with Defense, Homeland Security, State and foreign operations, military construction and Veterans Affairs, and Energy and water development.

“A lot of it will depend on how the CJS bill goes,” said Rep. Robert Aderholt (R-Ala.), chairman of the Appropriations Subcommittee on Homeland Security. “There’s such limited amount of time on the floor, and they think this might be a way to get it.”

At the same time, leadership is being pressured from the right not to bundle bills. Rep. Tom McClintock gathered 43 House Republican signatories, many from the  conservative Republican Study Committee, on a letter sent Tuesday to Speaker John Boehner (R-Ohio) and Cantor asking that appropriations bills be brought to the floor individually.

“I believe in the process. The process has evolved over centuries to distill good decisions from many diverse viewpoints,” the California Republican said in an interview. “One of the reasons we’ve got into this mess as a country is that we’ve put this process aside.”

The letter notes that Boehner called for doing away with comprehensive spending bills and in his 2010 “Pledge to America” promised to offer legislative issues one at a time and allow Members to offer amendments to cut spending.

Rep. Trey Gowdy, who signed the letter, said he wants an open process to slam Attorney General Eric Holder with appropriations riders to influence him into releasing documents related to the “Operation Fast and Furious” gun surveillance program.

“To quote John Boehner, ‘letting the House work its will,’” the South Carolina Republican said. “It’s slow, it’s deliberate. I just think it’s the best way to do it.”

The letter did not explicitly say Members would vote against a package, but McClintock said bundling the bills would increase the chances he would vote “no.”

In that case, Republicans might have to rely on Democrats to pass appropriations bills, as they did last year. But the landscape changed when Republicans capped fiscal 2013 spending at $1.028 trillion in the House-passed budget.

Appropriations ranking member Norm Dicks said he will try to help pass as many bills as he can.

“They’ve worked with us. We’ve helped put the bills together. We’re trying to be constructive,” the Washington Democrat said.

But Minority Whip Steny Hoyer said that going back on last year’s agreement to set spending levels at $1.047 trillion angered President Barack Obama.

“The administration has indicated, as a result, that it is inclined to not support bills that do not reflect the agreement, and therefore do not reflect investment in the priorities we believe in,” the Maryland Democrat said. “I agree with the president on this, personally. We made an agreement, a compromise.”

Even so, there is no guarantee that bundling bills could save time, Appropriations Subcommittee on Financial Services Chairwoman Jo Ann Emerson noted. Instead, it would simply ensure that leadership has to muster 218 votes only once, rather than several times.

“I’m not sure how it makes it more efficient,” the Missouri Republican said. “The only difference is that we have one final vote maybe, but you’re still going to have all these people still offering amendments.”

Bundling could help pass a bill such as State and foreign operations, which cuts some foreign aid programs, a move decried by Democrats. But it could just as easily endanger other bills’ chances of passage.

Appropriations Subcommittee on Defense Chairman Bill Young said he thinks it would be easier to pass his bill as a stand-alone because it usually passes with bipartisan support every year.

“This bill is clean, there’s no earmarks,” the Florida Republican said. “I think the Defense bill should be the Defense bill and it should be handled as such.”