Washington, D.C. ? The spending barons on Capitol Hill, long used to muscling past opponents of bills larded with pet projects, are seeking one last victory before tea party-backed GOP insurgents storm Congress intent on ending the good old days of pork-barrel politics.

You might call it the last running of the old bulls in Congress.

In the waning days of the lame duck congressional session, Democrats controlling the Senate — in collaboration with a handful of old school Republicans — are pushing to wrap $1.27 trillion worth of unfinished budget work into a single “omnibus” appropriations bill.

Their 1,900-plus-page bill comes to the floor this week stuffed with provisions sought by lawmakers. It contains thousands of pet projects, known as earmarks, pushed by Democratic and GOP senators alike — despite a pledge by Republicans to give up such projects next year.

“That omnibus bill will be loaded down with earmarks and pork-barrel spending, which is a direct — a direct — betrayal of the majority of voters on Nov. 2 who said ‘Stop the earmarking, stop the spending, stop the pork-barrel projects,'” protested Sen. John McCain, R-Ariz.

Altogether, the bill contains about $8 billion worth of earmarks, less than in previous years since House Republicans didn’t ask for any. The earmarked funds equal less than 1 percent of the measure.

The catchall bill is designed to bankroll the operations of every Cabinet agency for the budget year that started Oct. 1, as well as $158 billion to pay for wars in Afghanistan and Iraq.

It also challenges President Barack Obama. One administration-opposed provision would block the Pentagon from transferring Guantanamo Bay prisoners to the United States. Another would provide $450 million for a program to develop a second engine for the F-35 Joint Strike Fighter despite a veto threat by the administration, which says it’s a waste of money.

The architect of the measure, Senate Appropriations Committee Chairman Daniel Inouye, D-Hawaii, has been working with senior Republicans on the panel — Thad Cochran of Mississippi, Robert Bennett of Utah and Kit Bond of Missouri, among others — to line up the 60 votes needed to repel a filibuster promised by GOP Sen. Jim DeMint of South Carolina and other conservatives.

“We remain cautiously optimistic,” said Inouye spokesman Rob Blumenthal.

Inouye’s optimism was based on earlier private conversations with Democrats and Republicans alike, but it remains to be seen whether key Republicans will stick with him in the face of fierce opposition from tea party activists. But Inouye allies like Bennett, Bond and George Voinovich, R-Ohio, are already leaving politics.

Inouye’s measure would replace a slightly less expensive bill that the House passed last week. The House bill doesn’t contain earmarks like road and agricultural research projects, water treatment plants and grants for local anti-drug campaigns.

House Democrats, however, would gladly accept the fatter Senate version. Its many earmarks include $80 million in grants to states and Indian tribes to preserve Pacific salmon and $13 million in clean water grants for rural and Alaska native villages.

There’s also $4 million sought by Senate GOP leader Mitch McConnell for the Kentucky National Guard’s marijuana eradication efforts and $8 million sought by GOP Sen. John Thune of South Dakota to help maintain the B-1 bomber fleet in his state. Though their states would benefit, both Republicans oppose the bill, and McConnell said Tuesday he’s asked for his earmarks to be removed.

“This is exactly what the American people said Nov. 2 they didn’t want us to do,” he added.

The year-end logjam continues a long tradition in which a dysfunctional Congress is unable to do its most basic job of providing money to run the government on time.

Rather than debating a dozen separate appropriations bills, the omnibus spending measure rolls all the spending bills into a single piece of legislation that is likely to be brought to the floor in a way that keeps opponents from trimming it down.

Democrats hope to pass the measure by a midnight deadline Saturday. That would give them the latest — and perhaps last — victory over conservatives who contend the annual appropriations bills spend too much money and contain too many pork-barrel projects.