By Annika McGinnis and David Lawder
WASHINGTON, July 13 (Reuters) - This year was supposed to be different for Congress.
U.S. lawmakers expected that a promising budget deal reached after a government shutdown last year would herald a new normal for passing annual spending bills, moving Congress away from the crisis-driven approach and resulting economic jitters of recent years.
But the spending bills have been derailed in the Senate by election-year politics and a war over Republican amendments that range from thwarting curbs on power-plant carbon emissions to restoring potatoes to a government nutrition assistance program.
With a new fiscal year looming on Oct. 1, a stopgap funding measure of the type that has kept the federal government afloat in fits and starts for five years looks increasingly likely, along with the risk of another government shutdown.
Congress starts a five-week recess on Aug. 1 and has about 10 work days in September before lawmakers break for a month of campaigning for November congressional elections.
"Prospects don't look good at the moment" for the 12 spending bills, said Senator Richard Shelby, the top Republican on the Senate Appropriations Committee. "This is an election year and this is tough politics."
Nothing has illustrated that sentiment more vividly than the brawl over an amendment fighting new Environmental Protection Agency rules to curb power plant carbon emissions that Senate Republican leader Mitch McConnell tried to attach to a package of three spending bills.
McConnell, locked in a heated re-election fight in coal-rich Kentucky, argued that a simple majority for amendments should apply to appropriations bills, rather than the 60-vote threshold he has insisted on in the past.
As the pro-coal amendment was likely to draw significant support from Democrats also facing re-election battles, Senate Majority Leader Harry Reid refused to budge on the 60-vote threshold and pulled the three bills from the floor in June.
The two sides remain deadlocked.
Ross Baker, a political science professor at Rutgers University in New Jersey, called the dispute election-season "trench warfare," with Reid moving to protect his vulnerable majority from votes that might cost Democrats seats in November.
Lawmakers had seen a strong chance of properly executing their constitutional spending powers this year because the post-shutdown budget deal had set top-line spending levels for discretionary programs for two years, eliminating a major source of division. All they had to do was divide up the money.
Now some on Capitol Hill are wondering what lawmakers' work will come to this year if that opportunity is squandered. Allocating taxpayers' money makes up a significant part of Congress's work: about a third of the House of Representatives' roll call votes so far this year, 115 out of 378.
"It seems to me we spent all week doing, so much of the time, nothing," Reid said during an appropriations debate last month. "Sadly, I am sorry this is the norm around here."
Things are somewhat better in the Republican-controlled House, where six of 12 spending bills have passed. But the latest, a $34 billion energy and water programs bill approved on Thursday, drew a veto threat from the White House because it included provisions to block some new environmental regulations.
The last time Congress succeeded in passing all 12 bills on time was in 1996. In almost 40 years, lawmakers accomplished the task just four times.
Greater political polarization has increased Congress's reliance on stopgap measures to fund the government, political science professor Sarah Anderson found in a 2012 study at the University of California, Santa Barbara.
Anderson said spending bill delays are even longer when one party is split. With the rift between mainstream Republicans and the conservative Tea Party wing, the situation now is "probably pretty close to as bad as it gets," she said.
Senate Appropriations Committee Chairwoman Barbara Mikulski, a Democrat, is refusing to give up on the spending bills. She insists she has not started work on a continuing resolution, or CR, to extend funding past Sept. 30.
A CR would rely on the previous year's funding levels until lawmakers hammer out a final bill. This places a burden on federal agencies, making it impossible for them to carry out some basic functions such as hiring because of budget uncertainty.
Mikulski did not rule out an "omnibus" spending bill that combines individual appropriations bills and acknowledged that amendments are threatening to derail the process.
"For anybody that has other amendments, leave us alone. Let us get our bills done," she implored in a committee hearing on Thursday.
The same politics driving those legislative embellishments - looking good in an election year - may help avoid a government shutdown a month before voters go to the polls.
"I think both parties would ultimately vote for a CR," said Shelby, who is from Alabama. "Nobody wants to shut the government down." (Editing by Doina Chiacu and Mohammad Zargham)