WASHINGTON (AP) — Conservatives dominating the House are pushing to scrap last year's budget pact with President Barack Obama and impose new cuts on domestic agencies in an election-year drive to show voters they're serious about shrinking the government.

The move is popular with freshman lawmakers elected on a tea party wave in 2010. But veteran lawmakers warn it will produce gridlock later, when Congress has to follow up the springtime debate on a broad budget blueprint with actual spending bills reflecting the new cuts, and get them enacted into law.

Driving the discussion is frustration among many Republicans that they haven't done enough to cut spending or curb deficits that still exceed $1 trillion a year. The upcoming budget debate is maybe the last, best forum to demonstrate their bona fides to voters — especially core conservatives they're counting on to turn out in large numbers to maintain the GOP's majority in the House.

"There is a lot of pent-up demand from our members to show the American people a way forward to fiscal sanity. We can't continue to have budget deficits of over a trillion dollars a year," House Speaker John Boehner, R-Ohio, said Tuesday. "This is not sustainable. So our members want to show the American people a way forward, and they will."

At issue is the arcane way Congress does its annual budget. First comes a debate on a sweeping but nonbinding document that's called a budget resolution. It sets the broad parameters for follow-up legislation on spending and taxes.

Last summer's hard-fought legislation to lift the government's borrowing limit also set 10 years' worth of new, stringent "caps" on the Cabinet agency budgets set each year by Congress. Lawmakers followed it up in December with a $1 trillion-plus omnibus 2012 spending package that essentially froze day-to-day agency operating budgets.

In the eyes of Democrats, the White House and many Republicans, a deal's a deal — the $1.047 trillion agency spending cap for fiscal 2013 should govern the upcoming round of spending bills.

A large contingent of Republicans, however, never supported the underlying debt and budget deal. And they won't support a GOP budget plan that affirms it.

"The cap is a ceiling, not a floor. I think there are a lot of people in my conference that would not vote for it at $1.047 trillion just because of the frustration of that," said Rep. James Lankford, R-Okla. "We have got to address more aggressively the debt issue."

Added Rep. Mick Mulvaney, R-S.C., "We're just trying to argue that we're really serious about spending less money."

A key wrinkle this year is that because the so-called deficit supercommittee failed to agree on at least $1.2 trillion in spending cuts over the coming decade, a round of automatic across-the-board spending cuts will kick in next January. Much of the reasoning behind lowering the caps is that the automatic cuts — called a sequester — would effectively reduce the $1.047 trillion cap by almost $100 billion anyway.

The White House says Republicans should return to the drawing board and look at tax increases and other accounts rather than further cuts to domestic programs like education, homeland security, community development grants and housing subsidies for the poor.

"What Congress should be doing is coming up with a balanced package of deficit reduction that asks all to shoulder their fair share, not pursuing deeper cuts to education, medical research, food safety and other critical areas," said Moira Mack, a spokeswoman for the White House Budget Office. "If Republicans rewrite the caps, then it would be breaking the budget deal."

The potential magnitude of the looming cuts has many pragmatic-minded Republicans on the Appropriations Committee also pushing back.

"We made a deal at $1.047 trillion and my view is it should be $1.047 trillion," said Rep. Steve LaTourette, R-Ohio. "You're looking, at in some of these appropriations, a 50 percent cut over two years. I don't see how you write bills."