* Republicans push Obama to alter energy policies
* Leaders meet amid election-year acrimony
* Analysts skeptical about meeting's purpose (Adds quotes and details)
By Alister Bull and Richard Cowan
WASHINGTON, Feb 29 (Reuters) - President Barack Obama and Republican congressional leaders briefly put aside their election-year attacks on each other on Wednesday for a rare working lunch that the White House billed as an effort to find common ground on strengthening the economy.
The president and his fellow Democrats are at odds with Republicans over how to tackle high unemployment and nagging government budget deficits. Both sides are highlighting conflicting policy prescriptions to win over voters before the November elections.
Republican leaders used the event to point out their differences with Obama over U.S. energy policy amid a rapid run-up in gasoline prices that could damage the president.
And shortly before going to the White House, Senate Republican leader Mitch McConnell took to the Senate floor to blast Obama's energy policies for a second straight day. His speech was part of a coordinated Republican effort to exploit voter anxiety over rising gas prices.
House of Representatives Speaker John Boehner, the top U.S. Republican, told reporters later in the day that he urged Obama, as he has done many times over the past several months, to approve a stalled Canada-to-Texas oil pipeline project.
The president last month rejected the Keystone XL pipeline, which was to run through environmentally sensitive areas of Nebraska from the U.S.-Canadian border.
On Monday the White House said it welcomed a fresh proposal by TransCanada to build a southern leg of the pipeline and refile an application for the northern part of the route.
The bipartisan group did manage to focus on potential areas of agreement such as measures to help small businesses, which could be enacted this year.
"The president believed there were some areas that we could find common ground, and frankly I was encouraged by that," Boehner told reporters.
The White House also displayed some optimism.
"Certainly, there is reason to hope that if Congress can focus on resolving some differences, we could get some progress," White House press secretary Jay Carney said, referring to jobs proposals put forward by House Republicans.
The lunch meeting, the first between Obama and bipartisan congressional leaders since July 23, 2011, took place against the backdrop of escalating election-year rhetoric and continued partisan gridlock in Congress.
The luncheon might have been one of the few remaining opportunities in this election year for both parties to claim they made a stab at bipartisanship before the tone gets meaner.
"The American people tend to give presidents higher marks if they are part of the solution rather than part of the problem," said William Galston, senior fellow at The Brookings Institution in Washington.
"Having the president visibly reaching out his hand" could benefit Obama, he added.
The bickering that vexes Washington was underscored on Tuesday when moderate Republican Senator Olympia Snowe announced she would not seek a fourth term because she had grown tired of the partisan battles that have left Congress with an approval rating of around 10 percent.
The lunch was initiated by the White House, which said the aim was "to find common ground on legislative priorities that will create jobs and strengthen America's economy."
But even former administration officials, such as Jared Bernstein, Vice President Joe Biden's former chief economic adviser, expressed puzzlement at the purpose of the meeting.
"There is definitely a need for economic policy coming down from Congress, but the political constraints in an election year amplified by a level of partisanship that is as high as I've ever seen it, leads me to be very skeptical that we're going to see very much at all," he said.
Obama has made running against a "do-nothing Congress" a central plank of his re-election campaign. Analysts say Republicans, who get a bigger share of the blame for the Capitol Hill gridlock in polls, need to show voters that they can work with Democrats.
With surveys indicating voters are turned off by the failure of both parties to agree on even the most basic legislation, Obama is under pressure to show he can rise above the partisan fray.
Given the rancor in Washington, it might come as no surprise that congressional leaders left the White House unable to agree on what they had dined on.
"Red something - snapper," Senate Democratic leader Harry Reid told reporters. "Salmon," said Boehner. (Additional reporting by Donna Smith, Thomas Ferraro and Samson Reiny, editing by Xavier Briand)