President Obama will tout his administration's improvements in border security and renew a commitment to overhauling the nation's immigration system in a speech today on the U.S.-Mexico border at El Paso, Texas.
But with key voices on both sides of the debate saying there is little chance Congress will overhaul immigration laws any time soon, Obama's speech is widely seen at least in part as a political appeal to Hispanics, who are a key constituency for his 2012 reelection campaign.
Hispanics voted for Obama by a 2-to-1 margin in 2008. But many have since become disillusioned, hit hard by the sluggish economic recovery and disappointed by unfulfilled promises to improve policies affecting millions of legal and illegal immigrants and their families, community leaders say.
"In the immigrant community across the country, there is broad acknowledgment that Republicans are the single biggest impediment to bringing comprehensive immigration reform to a successful conclusion," Democratic Rep. Luis Gutierrez of Illinois said in an interview.
"But when we had broad, expansive Democratic majorities in both the House and the Senate, where was this call for reform from Obama? Where was the push to get Republicans to the table? Where was the energetic, 'Let's get out there and rev up the troops?'
"I'm past that. But I'm not going to participate in public announcements that I think bring about unrealistic expectations in the general population," he added, referring to Obama's speech.
White House officials say Obama has always been committed to achieving a comprehensive package of immigration system reforms, and will use the Texas event to issue a new "call to action." But they say he will not lay out specific policy ideas or a legislative deadline.
"We weren't able to achieve it in the first part of this term, the president's term, but it remains a priority of the president's, even though it's hard," White House press secretary Jay Carney said Monday of a broad legislative reform package.
Most Republicans and some moderate Democrats staunchly oppose any legislation that would address the legal status of the country's estimated 11 million undocumented immigrants, citing concerns about competition for scarce U.S. jobs and added strain on social welfare programs.
Still, Obama has held three high-profile meetings on immigration in recent weeks, pulling together a diverse mix of stakeholders and lawmakers from across the country to enlist help campaigning for his plan, and adding pressure on Republicans who oppose it.
Obama envisions a sweeping law that would make immigration enforcement programs more strategic, penalize employers who hire illegal workers, streamline the visa process and provide relief to thousands of immigrant families living in the shadows.
"This is the fourth week in a row the president has addressed immigration reform, clearly showing we're on the tracks for change," said Ali Noorani, executive director of the National Immigration Forum.
But with no legislative progress expected before the 2012 election, Noorani and other immigrant advocates want Obama to use his administrative powers to grant at least temporary relief to some undocumented immigrant students and family members of U.S. citizens.
They say he could use a presidential memorandum or executive order to shield selected immigrants from being targets for deportation and possibly remove barriers to a path to legal status in the United States for others.
The Political Risks for Obama
The White House said earlier this month the president would "carefully review" the requests put forth by immigrant advocates and members of Congress.
Opponents of legal and illegal immigration have warned, however, that such a move could cost the president politically.
"I think the president would be handing a tremendous political victory to his opponents for next year's election if he took some administrative action," said Roy Beck, president of Numbers USA, a group that seeks greater immigration restrictions. "Then, it won't just be about immigration, it will be about abuse of executive power.
"He knows no amnesty has any chance. They know it. But they are going around and wanting people to know that it's not his fault so that the pro-amnesty voters will come out and vote better than they did in 2010," Beck said of Obama's speech.
Noorani of the National Immigration Forum says Obama needs to take action to back up his words.
"I believe that they are having a serious conversation about what they can and should do," Noorani said. "But at the least, all these events Obama has been having put the burden on Republicans, and that's only a good thing."
ABC News' Sunlen Miller contributed to this report.