President Barack Obama has made an impassioned plea in Las Vegas for "common sense, comprehensive" immigration reform to give 11 million people already in the United States illegally, a path to citizenship and to make it easier for foreign students with degrees and bright minds to stay.
On his first trip since being sworn in for a second term, Mr Obama urged Congress to pass a reform bill as soon as possible and said he welcomed the efforts of a bipartisan group of eight US senators, four from each party, who came forward on Monday with their own overhaul plan. Drawing loud cheers at a local high school, however, he said he would make his own push on the issue if Congress fails to deliver.
"We need Congress to act on a comprehensive approach that finally deals with the 11 million undocumented immigrants who are in this country," the president said. "The good news is that – for the first time in many years – Republicans and Democrats seem ready to tackle this problem together."
For years one of the most intractable issues in Washington, immigration reform, is suddenly front and centre not least because of alarm in the Republican Party that Hispanics, the fastest growing ethnic group in the country, have turned against them, turned off by years of conservative, anti-immigrant rhetoric. Mr Obama, by contrast, won a new term partly on a wave of Hispanic support.
That the eight senators, who include on the Republican side Marco Rubio of Florida and John McCain of Arizona, have already stepped forward is significant. But pitfalls lie ahead. It remains to be seen, for example, whether they will be able bring enough people in Congress along with them. And if Mr Obama pushes too hard too quickly, the danger is that conservative Republicans will instinctively push back.
Even before Mr Obama spoke, Senator Mitch McConnell briskly warned him against "delivering another divisive partisan speech". Senator Rubio, seen by some as a likely contender for his party's nomination in 2016 in part because of his Cuban heritage, meanwhile accused the White House of trying to play down tightening border controls which the group has said must be a condition of offering citizenship.
"That would be a terrible mistake," he told Fox News. "We have a bipartisan group of senators that have agreed to that. For the president to try to move the goalposts on that specific requirement, as an example, does not bode well in terms of what his role's going to be."
Conservatives will also bristle if, as expected, Mr Obama seeks help for gay couples in visa trouble because one is American and the other is not. "The president has long believed that Americans with same-sex partners from other countries should not be faced with the painful choice between staying with the person they love or staying in the country they love," his spokesman, Jay Carney, said.
Arguments will surely also range over how long and how narrow the path to citizenship for undocumented people should be. In general terms, all sides envisage inviting those who are illegal to leave the shadows and seek permission to stay while getting to the back of the queue for legal residency. Mr Obama may want to see a simpler process than most Republicans will.
In his speech, Mr Obama looked back to earlier generations who were allowed to make America home. "The Irish who left behind a land of famine; the Germans who fled persecution; the Scandinavians who arrived eager to pioneer out west," he said. "All those folks before they were us, they were them."