A constitutional amendment requiring a balanced federal budget is the best way to force dawdling politicians to finally mop up the record red ink plaguing Washington. Or it is snake oil that would let those same politicians pose as serious deficit warriors while, as always, leaving the real work for later.

Either way, the proposal — a Washington staple for decades that as usual faces long odds for passage — took center stage Friday as a potent vote-getting device for conservatives. House Speaker John Boehner, R-Ohio, used it to swing GOP support behind his stalled debt bill as the House continued its epic clash with President Barack Obama and the Democratic-run Senate over federal borrowing and spending.

The idea is near-sacred dogma for many of the House's 87 GOP freshmen and the many conservative, tea party-backed Republican lawmakers. Balancing the budget was a cornerstone of many of their congressional campaigns last year, and the push for a constitutional amendment requiring balance has become emblematic of their legislative goal of shrinking government.

"You have to have something that sets forth a structure that requires us to be financially responsible," said Rep. Mo Brooks, R-Ala., one of several Republicans who pledged to back Boehner's bill on Friday because of the leadership's embrace of the amendment.

Many Democrats and outside budget analysts say the amendment would leave lawmakers with the same painful decisions they usually avoid making today — which programs to cut or taxes to raise. They say it would make it harder for the government to help avoid recessions by pumping money into the economy, which usually causes red ink. And it leaves unanswered how the balanced budget requirement would be enforced should a Congress and president disagree on how to do it.

"It is deeply flawed," Senate Budget Committee Chairman Kent Conrad, D-N.D., said Friday.

Supporters also argue that Washington should do no less than the states, all but a handful of which have balanced budget requirements. Critics counter that states face a far easier burden, since they don't wage wars or support the huge Social Security or Medicare benefit programs, and can also rely on federal aid.

Many budget experts warn that the nation's fiscal problems are too severe to await enactment of a balanced budget amendment.

Current versions of the amendment would not take effect for at least six years, a provision designed to give lawmakers time to adjust. But with today's annual deficits exceeding $1 trillion and the huge baby boom generation only beginning to retire and swell the costs of Social Security and Medicare, the government's I.O.U.'s demand action now, they say.

"We need to enact a real, large-scale deficit reduction plan this year," said Maya MacGuineas, president of the bipartisan Committee for a Responsible Federal Budget.

Boehner won conservative support for his debt bill on Friday by requiring that before the debt ceiling could be extended next year by $1.6 trillion, Congress must first approve a balanced budget amendment.

Republicans have two versions of the amendment this year, and Congress could vote on both. Facing strong Democratic opposition and a requirement for two-thirds House and Senate majorities, each is likely to lose.

One would simply require that government spending not exceed revenues.

This form has been around for years, including in 1995 when it came closest to passage as part of the GOP's Contract with America. It failed in the GOP-led Senate by a single vote when moderate Republican Sen. Mark Hatfield of Oregon voted no, saying he "did not want to trivialize the Constitution." The GOP-run House had passed it easily weeks earlier.

The other version ads two provisions beloved by conservatives but detested by Democrats. They would require two-thirds majorities for Congress to either raise taxes or allow spending to exceed 18 percent the size of the economy. Government spending has not been that small since 1966.

Three-quarters of the states must ratify constitutional amendments before they take effect.