WASHINGTON (AP) — Supporters of a far-reaching immigration bill in the Senate see fresh momentum from a report by the Congressional Budget Office that says the measure would boost the economy and reduce federal deficits by billions of dollars.

Congress' nonpartisan scorekeeping agency said Tuesday that the immigration bill would decrease federal red ink by $197 billion over a decade and $700 billion in the following 10 years as increased taxes paid to the government offset the cost of benefits for newly legal residents.

The White House said the report was "more proof that bipartisan commonsense immigration reform will be good for economic growth and deficit reduction." Several members of the "Gang of Eight" senators who drafted the legislation also welcomed the news.

The CBO assessment came as the pace of activity increased at both ends of the Capitol on an issue that President Barack Obama has placed at the top of his domestic agenda.

Challenged by protesters chanting, "Shame, shame," House Republicans advanced legislation to crack down on immigrants living illegally in the United States, while the Senate lurched ahead on a dramatically different approach offering the hope of citizenship to the same 11 million people.

The bill approved late Tuesday by the House Judiciary Committee on a 20-15 party-line vote would make being in the U.S. illegally a federal crime punishable by prison time, instead of a civil offense as it is now. It also would empower state and local law enforcement officials to enforce federal immigration laws.

Republicans said the bill was needed to ensure enforcement of the law and said the legislation was a first step in an incremental approach toward solving the immigration issue, in contrast to the comprehensive approach being taken by the Democratic-led Senate. Many in the Republican-controlled House oppose tackling the immigration issue with a single, big bill.

On Wednesday, the committee was to take up a bill creating a temporary agriculture worker program.

"There has to be a first step, Mr. Chairman, and enforcing the law seems to me a reasonable place to begin," said Republican Rep. Trey Gowdy of South Carolina, who wrote the bill approved Tuesday.

Democrats called the bill a dangerous retread of a similarly tough enforcement measure that sparked mass protests around the country in 2006.

Reading the bill, "you would think there are 11 million criminals in the United States," said Rep. Luis Gutierrez, D-Ill.

In the Senate, a bipartisan bill that Obama supports appeared on track for a final vote as early as July 4.

The CBO said in its report and accompanying economic analysis that the Senate legislation would raise economic activity in each of the next two decades, in part because of the legal immigration fostered by the measure and also because millions of workers currently in the country illegally would join the legal workforce and pay taxes.

The CBO said the bill would increase gross domestic product by 3.3 percent over the next 10 years compared with current law and by 5.4 percent over the following decade. The agency forecast that 8 million people now here illegally would gain legal status under the bill.

The CBO also said that average wages would decline through 2025 as a result of the bill and that unemployment would go up slightly.

One critic quickly seized on the impact on pay.

"It's going to raise unemployment and push down wages," said Sen. Jeff Sessions of Alabama, top Republican on the Senate Budget Committee. Supporters of the bill saw it differently.

Sen. Chuck Schumer, a New York Democrat and a member of the Gang of Eight, said the CBO report "debunks the idea that immigration reform is anything other than a boon to our economy and robs the bill's opponents of one of their last remaining arguments."

The report was issued near the end of a day of skirmishing on the Senate bill, during which senators rejected two amendments delaying legalization until certain security provisions were in place. One would have required additional fencing and the other a new biometric system to track entries into the country and exits.

Those proposals were overshadowed by a larger debate over the legislation's border security requirements, which Republicans generally want to toughen.

Sen. John Hoeven, R-N.D., is working on an amendment requiring the government to demonstrate an ability to apprehend 90 percent of those attempting to enter the country illegally before anyone already present can get a permanent resident green card.

Democrats have been skeptical of proposals along those lines, arguing that they could postpone legalization for years. But after intense discussions on the Senate floor, Sen. John McCain, R-Ariz., and others said they were hopeful of progress.

In addition to border security and a path to citizenship, the bill includes an expanded number of visas for highly skilled workers prized by the technology industry and a new program for low-skilled workers.