WASHINGTON - Homeland Security Secretary Janet Napolitano had just begun her remarks to a Senate Judiciary Committee hearing on immigration when the first protester leapt to his feet.

"You have destroyed our community!" he shouted. Others in the audience joined him, chanting, "Stop the deportations!"

The anger at President Barack Obama's deportation polices among some of his otherwise most ardent allies could pose a surprising complication to the delicate immigration-overhaul negotiations that are now underway.

The Obama administration's deportation record is provoking deep political tensions that could narrow the president's ability to make the concessions Republicans will likely demand as part of a comprehensive deal.

Under Obama, about 400,000 illegal immigrants are deported each year, a record rate. Administration officials contend the high numbers are linked to a massive expansion of resources devoted to immigration enforcement appropriated by Congress before Obama took office.

Latinos are widely credited with helping Obama win re-election, and there is high optimism among advocates about the prospects for immigration changes championed by the president.

But in a private meeting with Obama at the White House earlier this month, officials with the nation's leading immigration groups confronted the president directly.

One advocate told the president that the Hispanic community was "demoralized" by ongoing deportations, according to the several participants who spoke on condition of anonymity to discuss the off-the-record meeting.

"In a sense, the president is on borrowed time," said Chris Newman, legal director of the National Day Laborer Organizing Network.

Newman said that for many immigrants, Obama's policies were clearly preferable to Republican presidential nominee Mitt Romney, but "that doesn't erase the fact that there is tremendous apprehension about the dissonance between the president's rhetoric and his policies."

Administration officials say they've put in place policies that better prioritize deportation efforts, focusing on immigrants who have committed serious crimes, people who just recently crossed the border and others who had been caught repeatedly violating immigration laws.

Napolitano told senators last week that 55 percent of those removed in 2012 had been convicted of felonies or misdemeanors, and 96 percent fell within one of the agency's priority categories.

Last summer, Obama announced his administration would stop deporting many young adults who were brought to the country illegally as children and had committed no other crimes, a move that came partly in response to years of complaints from his immigrant supporters.

"This is something I've struggled with throughout my presidency," Obama told an activist who asked during a Google chat last week what the president would do to stop families from being split by deportations while the congressional debate inches forward.

"The problem is that, you know, I'm the president of the United States. I'm not the emperor of the United States. My job is to execute laws that are passed. And Congress right now has not changed what I consider to be a broken immigrations system," he said.

"We've kind of stretched our administrative flexibility as much as we can," he added "That's why making sure that we get comprehensive immigration reform done is so important."

In an interview Wednesday with the San Antonio Univision affiliate about the deportations, Obama was blunt: "At this point, I need Congress to act."

A new Pew Research/USA Today poll shows Obama's approval rating among Latinos is at 73 percent, up from 48 percent in late 2011.

Still, the continued wariness about deportations may help explain the impatience Obama has telegraphed to Congress about the need for quick action on changes to immigration laws.

Members of a bipartisan group of eight Senators have been working on a bill they hope to submit for hearings in March. But Obama has repeatedly said if their efforts drag, he will submit his own bill to Congress.

The seriousness of that pledge was demonstrated last weekend when a draft of Obama's back-up bill was leaked to USA Today. Republicans complained the emergence of White House plan made the bipartisan talks more difficult.

At the same time, in the delicate dance of Washington negotiations, the public pressure from immigrants also could help Democrats win what they consider a better deal by providing Republicans - more interested in the demands of their conservative base - a reminder that Democrats face pressures from their supporters.

"I'd be naive if I didn't think pressure from the left helps us at the bargaining table," said Sen. Dick Durbin, D-Il., a member of the Senate's bipartisan working group who asked Napolitano pointed questions about the administration's stepped-up deportations at last week's hearing.

"We hear every meeting about pressure from the right. We have to be sure everyone is sensitive to the need to make concessions," Durbin said in an interview.

The administration has long touted its stepped up enforcement efforts, partly to defuse Republican arguments that immigration change must wait until the border is more secure. Advocates believe that effort is bound to be futile.

Opponents, such as Sen. Jeff Sessions, R-Ala., argue the Obama administration has inflated deportation statistics by including those caught at the border and returned home along with those arrested farther in the United States.

Sessions contended the anger from activists is part of a coordinated campaign to create the impression that Obama has cracked down on illegal immigration, even as the administration introduces what he termed "backdoor amnesty."

"It is truly odd that we live in a time when the Executive Branch takes more seriously the protests of illegals against even weak enforcement of the law than it does the concerns of sworn law officers," he said in a statement.