WASHINGTON - Tuesday's House vote to keep the federal government funded for two weeks is the first step toward averting any imminent government shutdown, but it leaves the major differences between Republicans and Democrats over taxes and spending unresolved.

It also leaves tremendous uncertainty about what may happen next - whether the government will shut down later this month, or next, for want of funds, and whether the opposing sides can ever devise a long-term plan for reducing the national debt.

Tuesday's vote, aimed at preventing government funding from running out Friday, is little more than "kicking the can down the road," veteran budget analyst Charles Konigsberg said.

The Republican-controlled House voted, 335-91, to keep the government operating until March 18, while cutting $4 billion. The Democratic-run Senate plans to vote on the plan Wednesday or Thursday, and Majority Leader Harry Reid (D., Nev.) said it would pass.

Voting yes in the House were 231 Republicans and 104 Democrats; six Republicans and 85 Democrats voted no. All Philadelphia-area representatives voted for the extension except Rep. Robert E. Andrews (D., N.J.), who voted against it.

The House last month approved $61 billion in cuts through the rest of fiscal 2011, which ends Sept. 30, but Senate Democrats consider those cuts too severe, and the White House threatened a veto. That led to the two-week temporary solution while lawmakers seek common ground on funding for the remaining seven months of the fiscal year.

Ultimately, the fight over short-term spending is the first act in a more consequential drama - how to reduce federal debt over the long term. So far lawmakers have concentrated on cutting nonmilitary domestic discretionary programs that make up only 12 percent of the budget. They have not touched the big-money programs that drive up deficits - Social Security, Medicare, Medicaid, and defense - not to mention possibly raising taxes.

But lawmakers face two deadlines: Federal authority to borrow will run out later this spring, and fiscal 2012 begins Oct. 1. Both deadlines will force Congress to again confront tax and spending choices.

The longer that lawmakers deal with this year's spending, the less time they will have to craft a serious plan to address long-term issues, longtime budget analyst Stan Collender observed. Another worry is that this short-term debate will stiffen both sides, making later negotiations more difficult.

"We're frustrated that there's such a hue and cry over a very small part of the budget," said Robert Bixby, executive director of the Concord Coalition, a budget watchdog group. "It reinforces the perception that the problem is just waste, fraud, and abuse. In some ways, it's a substitute for a more serious budget debate they need to have."

Both sides Tuesday amped up their already-loud rhetoric. Senate Minority Leader Mitch McConnell (R., Ky.) called the House vote "an opportunity for House Democrats to admit the status quo isn't working."

Democrats fired back that if severe cuts were adopted, 2011 would be remembered as the year that "right-wing extremists defied common sense," said Rep. Ted Deutch (D., Fla.).

Also Tuesday, the Senate unanimously passed a bill to prevent lawmakers and the president from getting paid if the government shuts down.

The two-week cuts would affect a wide array of programs, including eliminating $1.24 billion for eight programs Obama did not propose funding in his fiscal 2012 budget blueprint. Among them: election assistance grants; an agriculture loan subsidy program; four education programs, including aid to smaller learning communities; and some federal highway money.

Also cut would be $2.7 billion for earmarks - lawmakers' pet projects - including Army Corps of Engineers construction, border patrol, and some Federal Emergency Management Agency programs.

Rep. Jason Chaffetz (R., Utah) said that he backed the two-week measure but that his patience was ebbing. "It's going to get tougher, not easier," he said. "There are some of us out there who won't play this game of $4 billion every two weeks."

Few appeared eager for a shutdown - or at least for being blamed for one. "The goal of House Republicans is not to shut down the government, but to rein in the out-of-control spending that is devastating our economy," said Rep. Renee Ellmers (R., N.C.).

The White House on Tuesday suggested doubling the length of the temporary fix to four weeks and the spending cuts in that period to $8 billion. But House Speaker John A. Boehner (R., Ohio) rejected the idea, saying it should have been floated sooner, not on the day of the vote.

The administration believes a shutdown - or constant threats of one - would hurt the economy and anger voters, White House press secretary Jay Carney said. He said President Obama did not want "a toll booth, where we are negotiating again and again on continuing resolutions to fund the government for two weeks or another short-term period. . . . The focus needs to be on the longer-term deal."

The two-week extension would expire on the eve of Obama's planned five-day visit to Brazil, Chile, and El Salvador. If congressional negotiators can't agree by then on a new funding measure, that would put him in a delicate bind. If the government shuts down, he will feel obliged to stay home to manage things. But if he does that, he will risk offending foreign partners.