Boxed in by their Senate colleagues on one side and House conservatives on the other, House Republican leaders are starting the slow march toward the Budget Control Act without explicitly walking away from their own House-passed budget.

Members across the ideological spectrum agree: House Appropriations Chairman Hal Rogers (R-Ky.), who wanted to stick to the BCA, and Budget Vice Chairman Scott Garrett (R-N.J.), who helped cut the budget cap to $1.028 trillion, said they anticipate a short-term continuing resolution in September at the BCA’s fiscal 2013 spending level of $1.047 trillion.

That eventuality was reinforced last week when Senate Minority Leader Mitch McConnell (R-Ky.) voted for that spending mark in the chamber’s Appropriations Committee, and President Barack Obama threatened to veto bills that don’t adhere to the BCA.

In the meantime, however, Rogers is walking a fine line. He wants to pass all 12 spending bills, and he must pass at least some to have leverage in negotiations with the Senate over a continuing resolution. To do so, he needs House Democratic votes because many Republicans routinely vote against spending bills.

Appropriators will release subcommittee allocations this week, and within the topline number of $1.028 trillion, Rogers and his cardinals are front-loading some of the bills with modest spending cuts or even increases to lure Democrats. Others will likely have deep cuts to appease fiscal conservatives.

“These bills are going to be going up and down,” Rogers said. “We’ll have some bipartisan support on some of the bills, some we won’t. … And that’s the nature of this place — work with what you’ve got.”

Already, the Energy and water development spending bill got a bump from last year to $32.1 billion, and Appropriations ranking member Norm Dicks (D-Wash.) said he will support it. The Commerce, Justice and science bill was cut modestly, and those two bills’ funding resembles the Senate versions, marked up under a $1.047 trillion cap.

More bills with Republican priorities, such as Defense, Homeland Security and military construction and Veterans Affairs, may be funded akin to current levels. That will probably leave the brunt of the cuts with controversial bills covering the Health and Human Services Department and the Environmental Protection Agency.

However, that approach could draw the ire of conservatives who, as one GOP aide put it, will “raise hell” if they suspect the committee of corralling spending cuts in bills that do not have a good chance of passing.

“We have a history of pointing out the hypocrisy of front-loading and how it leads to higher spending,” the aide said. “They underfund the later bills, people get outraged when we get to them, they get plussed-up, then the overall spending is higher.”

Rep. Mick Mulvaney said that happened with the Labor, Health and Human Services, and Education bill last year, and he hopes history will not repeat itself.

“That would be extraordinarily disappointing and something we’d have to talk about with leadership because we were told that wouldn’t happen this year,” the South Carolina Republican said.

Similarly, the Obama administration warned Rogers against front-loading bills in a letter from Office of Management and Budget Director Jeffrey Zients, in which he said the House’s budget resolution allows for only two options.

“Every appropriations bill will provide inadequate funding, or some bills will provide adequate funding so that other bills will face even deeper, more problematic cuts,” he wrote. “Both approaches break last summer’s agreement, and neither is acceptable.”

Still, Garrett, a leader within the conservative Republican Study Committee, said he can support the bills with the assumption that a short-term CR will ensure the $1.047 trillion spending level is not locked in for a full year. If presumptive GOP presidential nominee Mitt Romney beats Obama and Senate Majority Leader Harry Reid (D-Nev.) loses his majority, Republicans can cut even more spending, he said.

“The best win is a short-term. Let’s start in January,” he said. “You’re hoping for Romney coming in, and you’re hoping that Reid is being replaced, and you’re hoping that we’re making substantive changes.”

In the Senate, Democrats rejoiced when McConnell joined all but two of the 14 Republican appropriators at last week’s committee markup to vote for the BCA spending levels, a move Democrats said united Senate Republicans with Democrats against the House GOP budget.

But Senate Republicans rejected that characterization and said their vote was prompted by an effort to get the fiscal 2013 spending bills to conference, where the House GOP majority would work to cut spending below the BCA level.

Republicans have argued that the limits function as caps, above which appropriators cannot spend. However, Congress is permitted to spend below the levels if savings can be found, and a spokesman for McConnell said not to interpret his vote as an endorsement of spending all the way up to the limit.

“The Leader supports any effort to spend less than the maximum allowed, and Thursday’s vote prevents Democrats from spending any more than the BCA-agreed ceiling,” a McConnell spokesman said. “And we’d like to get these bills into conference with the House so that the conversation on reducing spending can begin.”

Sen. Lisa Murkowski (R-Alaska), ranking member of the Appropriation Subcommittee on the Interior and Environment, said Thursday that she believes “while we have these caps that are now adopted, I think we will all be looking how we can achieve further savings.”

A Senate Democratic aide said Friday that the vote amounted to a “welcome rebuke of the House Republican budget.”

“It’s fine by us if they want to distance themselves from the vote, but nevertheless their votes were with us,” the aide said.

The aide also suggested that the vote could have been influenced by election-year politics, with Republicans trying to avoid a repeat of last year’s government shutdown standoff, when a disagreement over funding the government led to a series of short-term spending extensions and much heated rhetoric.

“We view the vote as a major step forward toward averting a government shutdown,” the aide said. “I would not be surprised if Republicans coordinated with the Romney campaign in an effort to avert a shutdown before the election.”

Sen. Patrick Leahy (D-Vt.), chairman of the Appropriations Subcommittee on State and Foreign Operations, said he was not surprised by the GOP vote because he said Republicans did not want a repeat last of summer’s debt fight. “They looked silly,” Leahy said.