WASHINGTON (By Helene Cooper, NYT) April 28, 2010 ― President Obama conceded Wednesday that Congress may not have the appetite to deal with the hot-button immigration issue this year, but he vowed to continue to press lawmakers to at least begin work soon on a comprehensive bill to overhaul the country’s immigration system.

In a rare interview with reporters aboard Air Force One, Mr. Obama said it was vital that Congress address the immigration issue, lest more state measures like the tough new law in Arizona sprout up.

But he acknowledged that the road to a comprehensive immigration bill was an uphill one. “It’s a matter of political will,” he said, adding that Congress might not have the stomach for another tough battle after the bruising fight over health care and the prospect of another battle over a climate change bill.

“We’ve gone through a very tough year, and I’ve been driving Congress pretty hard,” Mr. Obama said.

But the president said “we need to start a process, at least,” adding he wanted to come up with a proposal that could win broad public support.

To succeed, Mr. Obama said, he will need some backing from Republicans, a tough task in an election year.

“I’ve made calls to Republicans,” Mr. Obama said. “I think I can get a majority of Democrats, but I need some help from Republicans.”

The Senate majority leader, Harry Reid, a Democrat who is locked in a bruising re-election campaign in Nevada, has promised Hispanic voters in his state that he will take up immigration legislation this year, addressing both border security and citizenship.

But on Wednesday, he told reporters that the climate change bill would probably come before immigration because that legislation had already been drafted.

He added, however, that Senator Charles E. Schumer, Democrat of New York, had an outline of an immigration bill that could soon be completed.

The immigration issue has become a lightning rod for both Republicans and Democrats, who are embroiled in a fight over a new Arizona law giving the police the authority to detain people they suspect are illegal immigrants.

Asked whether the White House, which has strongly criticized the Arizona bill as a possible infringement of civil rights, planned to challenge the measure, Mr. Obama said Wednesday, “We’re examining it now.”

He added, “I understand the frustrations of the border states,” but said that is why the country needed a comprehensive immigration overhaul.

Meanwhile, former President Bill Clinton waded into the debate on Wednesday with the bravado of someone never facing election again.

“I don’t think there’s any alternative but for us to increase immigration,” he said, both to help the economy grow and to fix the long-term finances of Medicare and Social Security.

“I just don’t see a way out of this unless that’s part of the strategy,” he added in his remarks at a meeting on fiscal policy in Washington.