By ANDY SULLIVAN Jul 6th 2015 10:53AM

Republican 2016 presidential hopefuls Scott Walker and Rick Santorum are suggesting a potentially controversial way to boost Americans' job prospects: admit fewer legal immigrants into the United States.

The notion, absent from presidential politics for at least 20 years, could help them tap into the frustrations of working-class voters who have struggled with stagnant wages and reduced job opportunities since the economic crisis of 2007-2009.

It could also complicate prospects for a comprehensive fix to the nation's outdated immigration system and tar the Republican Party as anti-immigrant at a time when it needs to broaden its support base of Hispanics and Asians, two of the biggest groups of legal immigrants in the United States.

"This hurts our efforts. I think people need to tone down the rhetoric," said Hugo Chavez-Rey, chairman of a Hispanic Republican group in the battleground state of Colorado.

Since 1989, the United States has been letting in about 1 million new immigrants per year, a level comparable to the last great wave of European immigration at the turn of the 20th Century. The Census Bureau estimates there are now 43.3 million foreign-born residents in the United States and within 10 years immigrants will account for 15 percent of the population, a record high. (Graphic:

Roughly 2 in 5 Americans think those levels are too high, according to polling by Gallup.

Many Republican presidential candidates are vocal champions of legal immigration. Former Florida Governor Jeb Bush, the front runner in the Republican race, says more legal immigrants are needed to boost economic growth while South Carolina Senator Lindsey Graham says they can help care for an aging population.

Kentucky Senator Rand Paul has said higher levels of legal immigration would lead to lower levels of illegal immigration, while former Arkansas Governor Mike Huckabee said "let's get as many people here as want to come" last month. Florida Senator Marco Rubio and Texas Senator Ted Cruz frequently invoke their Cuban-immigrant parents in stump speeches, and both have called for expanding guest-worker programs.