Compared with the Bush administration, Obama officials have substantially cut back on job-site roundups of illegal workers in favor of less controversial measures, such as auditing employers' books and expanding programs that target unauthorized immigrants.

Obama officials have not halted work-site roundups altogether, and their other enforcement programs continue to sweep up tens of thousands of non-criminal illegal immigrants. This has fueled a growing sense of betrayal among many Hispanics who voted for the president.

Among the advocates, much of the frustration stems from the stalled effort to legalize unauthorized immigrants as well as gnawing doubts about the president's commitment to push it through Congress this year. But perhaps no aspect of the immigration issue arouses more passion than the administration's enforcement record, because it is the one area over which the president has full control.

"When Obama said during the campaign it's un-American to tear a mother from her child, we believed him," said Angelica Salas, executive director of the Coalition for Humane Immigrant Rights of Los Angeles, which has brought several hundred protesters to Washington. "We never imagined a year later, we'd be denouncing his administration for surpassing the Bush administration on enforcement."

In recent months, a drumbeat of reports about small-scale work-site raids by ICE, including an operation targeting two Maryland restaurants last week in which agents arrested 29 foreigners, has also displayed the extent to which such actions still take place.

A recent government report that grossly overstated the rate of deportations didn't help matters, asserting deportations were up 47 percent in Obama's first year. This month, immigrant advocates seized on that statistic at a Washington news conference.

But as ICE officials clarified that day, deportations have increased by 5 percent, reaching 387,790 removals in fiscal year 2010. The increase in removals is due to a 19 percent rise in deportation of criminal immigrants, but two-thirds of those removed were still non-criminals, and the total reached a record high.

The record of ICE's fugitive operations teams is mixed. The teams, which search for illegal immigrants who have evaded deportation orders, have long been criticized for bursting into the homes of non-criminal immigrants instead of targeting dangerous criminals. Under Obama, the share of criminal immigrants arrested through fugitive operations increased from less than a fourth to nearly half. Yet non-criminal immigrants continue to account for the majority of arrests, numbering nearly 20,000.

Immigrant advocates have also expressed strong reservations about the administration's shift toward auditing company employment records. The number of such audits nearly doubled in the fiscal 2010, to 1,444, with 52 companies fined for employing illegal workers.

Even programs that would appear to focus on criminal illegal immigrants have aroused the ire of immigrant advocates. They note that under the Criminal Alien Program, in which ICE agents visit prisons to identify illegal immigrants, more than half of the 232,796 immigrants targeted for deportation in fiscal 2010 were non-criminals.