* Napolitano to push legislation in Congress
* McCain says reform must include temporary worker program
* Failure to pass may delay issue for generation -senators
By Doug Palmer
WASHINGTON, June 25 (Reuters) - President Barack Obama tapped a top Cabinet official on Thursday to work with Congress to speed immigration reform as senators warned another failed effort could doom chances for a generation.
"Despite our inability to get this passed over the last several years, the American people still want to see a solution," Obama told reporters after meeting with Democratic and Republican lawmakers.
Obama said he had asked Homeland Security Secretary Janet Napolitano to meet regularly with lawmakers to systematically work through a number of controversial issues, such as how to handle the 12 million illegal immigrants already in the United States and how to prevent future illegal immigration.
"It's going to require some heavy lifting. It's going to require a victory of practicality and common sense and good policymaking over short-term politics," Obama said.
Congress failed in 2006 and 2007 to pass immigration reform despite a push by former Republican President George W. Bush.
Earlier this year, Vice President Joe Biden said the U.S. economic slump and soaring unemployment made it a bad time to take on the issue, which stirs up strong emotions on both sides of the immigration debate.
But Obama, who has been criticized for not following through on a campaign pledge to tackle the issue this year, said the White House and Democratic-controlled Congress need to start pushing now to pass legislation and "not put it off for a year, two years, three years, five years from now."
Senator John McCain, the Republican who lost to Obama in last year's presidential election, told reporters the reforms also must include a temporary worker program for agricultural and high-tech industries that rely on non-U.S. citizen labor.
"I can't support any proposal that doesn't have a legal temporary worker program and I would expect the president of the United States to put his influence on the unions in order to change their position," McCain said.
Democratic Senator Charles Schumer told reporters after the White House meeting that Obama had set a goal of passing legislation by the end of this year or early next year.
If Congress cannot meet that deadline, "we may not get to do it for a generation," Schumer said.
Senator Lindsey Graham, a Republican, also said he saw only "one more chance" to pass a bill because of the political heat that immigration reform stirs up.
"If we can't get it done this time around, no politician is going to take this up in a generation. That would be a shame for this country," Graham said. (Editing by Mohammad Zargham)