WASHINGTON — In one of their final actions before leaving town to finish campaigning, senators voted early Saturday morning to approve a temporary spending measure that eliminates the threat of a politically embarrassing government shutdown one month before Election Day.

But the legislation passed without the support of Maine Republican Sens. Olympia Snowe and Susan Collins, both of whom cast votes against the stopgap measure to signal their dissatisfaction with Congress’ inability to pass complete budgets. The budget extension now goes to President Obama for his signature.

“It’s inconceivable and incomprehensible that we would be at a point here in the United States Senate where we are considering a six-month continuing resolution without having passed a budget, without having enacted any one of the 12 appropriation bills and spending so little time in session,” Snowe said following an earlier vote on the budget resolution.

The 62-30 vote came a few minutes shy of 1 a.m. after Democratic and Republican Senate leaders spent much of the day — and the week – battling over unrelated bills and staving off a one-man filibuster by Sen. Rand Paul, R-Ky., who was trying to limit U.S. aid to Libya, Pakistan and Egypt.

Another bill relating to sportsmen also slowed the process on Friday. Although it appears to enjoy strong bipartisan support, the measure became entangled in pre-election politicking as both sides attempted to keep the other from scoring points with voters.

The only must-do item on the get-out-of-Dodge agenda was a six-month spending measure to fulfill the bare minimum of Congress’ responsibilities by keeping the government running after the current budget year ends on Sept. 30.

The spending measure permits spending on agency operating budgets at levels agreed to under last summer’s hard-fought budget and debt deal between Obama and Capitol Hill Republicans. That’s an 0.6 percent increase from current spending rates, which represents a defeat for House Republicans, who tried to cut about 2 percent from the budget deal and shift $8 billion from domestic programs to the Pentagon.

Earlier in the week, Collins said in a Senate floor speech that Congress’ failure to complete any work on the budget bills would only reinforce the public’s perception of gridlock in Washington. Although she said she opposed a government shutdown, Collins said Congress was abdicating its responsibility.

Collins laid much of the blame on Senate Majority Leader Harry Reid, D-Nev., who has not scheduled floor debate on any of the 11 budget bills that passed the Senate Appropriations Committee, on which she sits. The House passed seven of its 12 budget bills.

“Given the state of our nation’s economy, and the need to ensure that tax dollars are wisely and appropriately spent, it’s unacceptable that we would simply agree to put our government on autopilot rather than work together to establish priorities and to make the tough choices to evaluate programs and restrain spending,” Collins said.

After the final early-morning votes, senators followed their House counterparts and left town until after the November elections. The Associated Press reported it is the earliest pre-election exit by Congress from Washington since 1960 and comes amid one of the most partisan, least productive sessions in recent memory.

The approval rating for the current Congress in a Gallup poll earlier this month sank to just 13 percent, the lowest ever for an election year. The GOP-controlled House and Democratic Senate managed to come together with Obama to enact just 173 new laws. More are coming after the election, but the current tally is roughly half the output of a typical Congress.

Snowe, who is retiring in January after more than 30 years in Congress, recalled that in 2000 — also a presidential election year — Congress was in session until the week before Election Day. And in 1990, lawmakers were in session most weekends before the election, she said.

“This has serious and significant implications when you pass a budget … for a temporary period of time instead of for the entire year, because it puts every agency, every person who depends on these programs in limbo because they do not know how much they will get,” Snowe said.

Snowe said that was brought home to her earlier this year when, during a visit to community assistance agencies, she spoke to a woman whose young child contracted pneumonia because she was not able to receive enough assistance to fill her heating oil tank due to agency uncertainty over funding.

The exit from Washington leaves the bulk of Congress’ agenda for a postelection session in which it’s hoped lawmakers will be liberated from the election-year paralysis that has ground Capitol Hill to a near halt.

At the top of the lame-duck agenda was dealing with the so-called fiscal cliff, which combines the expiration of the Bush-era tax cuts on Dec. 31 and more than $100 billion in indiscriminate, across-the-board spending cuts, set to strike at the same time as punishment for the failure of last year’s deficit “supercommittee” to strike a deal.

Also left in limbo is the farm bill, stalled in the House due to opposition from conservative Republicans who think it doesn’t cut farm subsidies and food stamps enough and Democrats who think its food stamp cuts are too harsh.

The current farm act expires on Sept. 30, but the lapse won’t have much practical effect in the near term. Still, it’s a political black eye for Republicans, especially those from farm states like North Dakota and Iowa.

The lack of productivity of the 112th Congress was the result of divided government and bitter partisanship. Die-hard Republican conservatives eager to roll back Obama’s agenda barreled headlong into an official Washington still largely controlled by Democrats — and oftentimes seemed to limit the options of their own leadership with their intransigence. The looming presidential and congressional elections caused top leaders in both parties to play it safe and stick to party positions.

The result: Congress’ major accomplishments tended to be legislation that mostly extended current policies, like a highway bill passed earlier this year and bills demanded by Obama to renew a 2 percentage-point payroll tax cut and extend student loan subsidies.

Even this Congress’ signature accomplishment — a budget and debt deal enacted last summer to cut $2.1 trillion from the budget over 10 years — punted most of its difficult decisions to the future by tasking the supercommittee with finding at least $1.2 trillion in deficit savings.

And, after the supercommittee cratered, House Republicans walked away from the budget deal by pressing for further cuts to domestic appropriations and reversing some on the pact’s Pentagon cuts.

Meanwhile, in the Senate, Reid worked closely with the White House to use the Senate schedule for Obama’s political advantage, repeatedly forcing votes on closing tax breaks for oil companies and raising taxes on upper-bracket earners.

But Reid failed to schedule floor debates on any of the 12 annual appropriations bills and the Democratic-led chamber, for the third year in a row, failed to pass a budget.

Republicans also point to almost 40 items of House-passed jobs-related legislation sitting stalled in the Senate.

“They haven’t passed a budget in more than three years. They have no plan to save Medicare, no plan to stop all the tax hikes, and no plan to replace the sequester,” Boehner said. “This isn’t leadership. It is negligence.”

Democrats defending the Senate point out that the balky chamber managed several bills that the House would not, including a renewal of farm programs and legislation to overhaul the Postal Service and give it an infusion of cash to stave off insolvency.

“The reality is, for as closely as divided as this Senate is, we passed a large number of bipartisan bills this year, very important bills, but as you all know, it takes two chambers to pass a law,” said Sen. Chuck Schumer, D-N.Y. “On the other side, too many of the Congress members, particularly the tea party folks, think compromise is a dirty word.”