WASHINGTON | Seven weeks after the collapse of legislation in Congress, the outcry against illegal immigration is louder than ever. It is manifested by proposed clampdowns at the state and local level and an uproar over the arrest of an undocumented immigrant in the execution-style slayings of three New Jersey college students. Scores of organizations, ranging from mainstream to fringe groups, are marshalling forces in what former House Speaker Newt Gingrich, a Georgia Republican, calls "a war here at home" against illegal immigration, which he says is as important as America's conflicts being fought overseas in Iraq and Afghanistan. While most of the groups register legitimate concerns about the impact of illegal immigration on jobs, social services and national security, the intense rhetoric is generating fears of an emerging dark side, evident in growing discrimination against Hispanics and a surge of xenophobia unseen since the last big wave of immigration in the early 20th century. "I don't think there's been a time like this in our lifetime," said Doris Meissner, a senior fellow with the Migration Policy Institute and former commissioner of the U.S. Immigration and Naturalization Service. "Even though immigration is always unsettling and somewhat controversial, we haven't had this kind of intensity and widespread, deep-seated anger for almost 100 years." The Alabama-based Southern Poverty Law Center, which monitors hate groups, said the number of "nativist extremist" organizations advocating against illegal immigration has grown from virtually zero just over five years ago to 144, including nine classified as hate groups, such as the Ku Klux Klan and Aryan supremacists. Some senators who participated in the midsummer debate over President Bush's failed immigration bill said they were barraged with venomous mail. Sen. John McCain, an Arizona Republican who supported the bill legalizing undocumented immigrants, said he has received death threats because of his position. "It is unbelievable how this has inflamed the American people," McCain said in a speech Thursday at the Aspen Institute in Colorado. Eighty-three percent of immigrants from Mexico and 79 percent of immigrants from Central America think there is growing discrimination against Latin American immigrants in the United States, according to a poll conducted by Miami-based Bendixen & Associates. Instead of taking a downturn after the collapse of Bush's immigration overhaul in June, the debate over illegal immigration has continued and seemingly escalated. As prospects for congressional action appeared increasingly in doubt this year, all 50 states and more than 75 towns and cities considered -- and in many cases enacted -- immigration restrictions, even though initial court rulings have declared such actions unconstitutional intrusions on federal responsibilities. Two counties in the populous northern Virginia suburbs of Washington are among the latest to consider restrictions on immigration. Nationwide, many of the proposed ordinances strike a similar theme, penalizing employers who hire illegal immigrants, barring undocumented immigrants from certain municipal services, or prohibiting landlords from renting to illegal immigrants. The murders of three college students in Newark -- and the wounding of a fourth -- reignited calls for a clampdown on illegal immigration after disclosures that one of the suspects, Jose Lachira Carranza, was an illegal immigrant from Peru who was out on bail awaiting trial on assault and child rape charges.