After the Colorado shooting, two Democrats introduced a bill that would prohibit the general public from buying thousands of rounds of ammunition by mail or online.
Senate Majority Leader Harry Reid, a Democrat, said the Senate's schedule is too crowded to allow a debate on gun control this year and has been noncommittal about whether Congress would consider the issue next year. The White House has said President Barack Obama will not push for stricter gun laws this year.
U.S. Sen. Dianne Feinstein, a Democrat from California, complained after the Colorado shooting that Congress has failed since 2004 to renew the federal assault weapons ban she authored a year after a gunman killed eight people in a San Francisco high-rise in 1993.
Nor will Congress take up the bill introduced after the Colorado shootings by U.S. Sen. Frank R. Lautenberg of New Jersey and Rep. Carolyn McCarthy of New York.
"The reality is that these tragic shootings will continue if we can't break the gun lobby's stranglehold on Congress," Lautenberg said in a statement.
Since 1990, the National Rifle Association's political action committee and individuals associated with the NRA have contributed nearly $19 million to members or candidates for Congress, with 82 percent of those contributions going to Republicans, according to The Center for Responsive Politics in Washington, D.C.
The National Rifle Association did not respond to repeated messages left by The Associated Press over several days. Sam Paredes, executive director of Gun Owners of California, said the state's current laws are already working and don't need to be tougher. He cited a 2010 state attorney general's report that found less than 4 percent of the weapons used in violent crimes and sent to state crime labs were assault weapons.
"We're governed by people who have an inordinate fear, a knee-jerk, visceral, emotional reaction to guns," Paredes said.
The divide is not just between states and the federal government, but also between Democratic- and Republican-leaning states.
In Wyoming, for example, the Republican-dominated Legislature recently passed a bill allowing residents to carry concealed guns with no permit or background check. Texas Gov. Rick Perry, a Republican, defended gun rights even after a shooting this week near Texas A&M University that killed three people including a police official and the gunman.
Dan Gross, president of the Brady Campaign to Prevent Gun Violence, said the gun control proposals were a step in the right direction.
"There are places where we're seeing kind of the hopeful signs," he said. "But right now, there are far too few of them."
Associated Press writers Michael Gormley in Albany, N.Y.; Sophia Tareen in Chicago; Ben Neary in Cheyenne, Wyo.; and Will Weissert in Austin, Texas, contributed to this report.
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