WASHINGTON – Pro-immigration groups nationwide are girding for a major battle to stop or alter a Trump administration proposal unveiled over the weekend – weeks before November's midterm elections – that would strictly enforce rules for millions of immigrants applying for green cards or visas by scrutinizing their use of food stamps, welfare, housing vouchers or Medicaid.

Department of Homeland Security officials, who announced the proposal late Saturday, said their plan would save federal taxpayers $2.7 billion annually by deterring immigrants from applying for benefits they would otherwise be qualified for. It would affect about 380,000 people annually, according to federal officials, who said it is designed to ensure that immigrants can support themselves.

“Under long-standing federal law, those seeking to immigrate to the United States must show they can support themselves financially,” DHS Secretary Kirstjen Nielsen said. "This proposed rule will implement a law passed by Congress intended to promote immigrant self-sufficiency and protect finite resources by ensuring that they are not likely to become burdens on American taxpayers.”

In certain cases, federal officials said, people who are lawful permanent residents and who have received benefits could be subject to the new rule if they leave the country and try to return. Most green card holders would be unaffected.

The proposed rules, which run 447 pages, are slated to take effect after a 60-day public review and comment period.

The administration's proposal is in keeping with President Donald Trump's campaign promises to pursue tougher immigration policies, from building the wall on the southern border with Mexico to limiting the number of refugees, asylum seekers and other immigrants attempting to enter the country.

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Stricter immigration policies are viewed as a hot-button issue to bring conservatives to the polls, while Democrats see it as a lightning rod for motivating their base.

Immigrant advocates decried the proposal Sunday, describing it as “cruel” and blasting the administration, specifically White House aide Stephen Miller, for playing election-year politics by targeting millions of immigrants.

“This has Stephen Miller’s fingerprints all over it,” Frank Sharry, executive director of America’s Voice, a pro-immigration group. “He and his cabal of hard-liners are determined to keep out and kick out as many immigrants and refugees as possible.

“This strategy is not only cruel, it’s purposeful,” Sharry said. “Miller and the Trump White House believe pitting people of color against their supporters will improve GOP prospects in the 2018 midterms.”

Less than two months before midterm elections, polls show Democrats could take control of the Republican-controlled House of Representatives and are running close in very competitive Senate races. The GOP holds a 51-49 majority in the Senate.

Hard-line conservatives have long argued against admitting immigrants who can't support themselves. Immigrant advocates said it's an attack on some of the world’s most vulnerable people who seek a chance at a better life in the USA – and who might need a little help getting started.

The proposed Trump policy means immigrants will be "hungrier, sicker and poorer," said Olivia Golden, the executive director of the Center for Law and Social Policy. "It targets documented working parents who are playing by the rules. Everything that we know suggests that it's a terrible idea. We have to fight back."

For decades, immigration officials have considered applicants' financial status in deciding whether to permit them entry, but the new rules are significantly stricter.

Potentially disqualifying benefits include Medicare Part D prescription drugs, Medicaid with some exceptions for emergency services and disability services related to education, food stamps and Section 8 housing vouchers.

Critics contended that focusing on the immediate economic costs of immigration is short-sighted and ignores the long-term contribution immigrants make to society.

Supporters of the president's proposal said immigration advocates try to have it both ways by claiming immigrants are a net benefit to the country and simultaneously saying they need access to food stamps and housing assistance.

"Interesting how the same people who claim immigrants are such a fiscal benefit are now screaming that a huge percentage will be blocked because they are dependent on welfare benefits. Which is it?" tweeted Jessica Vaughan, the director of policy studies at the Center for Immigration Studies.

According to a study on the economic impacts of immigration conducted by the National Academies of Science, Engineering and Medicine last year, first-generation immigrants cost U.S. taxpayers $57.4 billion a year. But the researchers found that second-generation immigrants provided an economic boost of $30.5 billion and third-generation immigrants created a $223.8 billion gain.

The positive contribution of immigrants was underscored this year in a letter signed by 1,470 economists delivered to Trump and Republican leaders in Congress. The group acknowledged that in the short run, immigrants can prove harmful to some American businesses and American workers with lower levels of education.

"But the benefits that immigration brings to society far outweigh their costs, and smart immigration policy could better maximize the benefits of immigration while reducing the costs," the economists concluded.

Rep. Luis Gutierrez, D-Ill., said in a statement, "From the first day of the Trump campaign, the message has been that immigrants are a danger and a drain. Today he’s selling the lie that immigrants weaken the U.S. economy when exactly the opposite is true.”