DENVER (AP) -- The last time Colorado enacted gun control measures was in the wake of the 1999 Columbine High School shooting, and once the laws were on the books there was little acrimony.
The state's latest batch of gun control laws -- coming after a gunman's deadly rampage at a suburban Denver movie theater a year ago -- has sparked a struggle over guns that shows little signs of fading. Gun rights advocates are trying to recall two state senators who backed the package, and dozens of GOP county sheriffs are suing to overturn it.
"This is going to remain a political hot potato for Democrats for many, many months," said gun-rights activist Ari Armstrong.
Ironically, in the months after the gunman's shooting spree left 12 people dead and injured 70 others, there was little public discussion of gun control here. The shooting at a midnight showing of the Batman film "The Dark Knight Rises" occurred in a key swing county in one of the most hotly-contested battleground states in last year's presidential election.
But President Barack Obama, seeking re-election, did not bring up gun control in a state that cherishes its western frontier image. Neither did most Colorado Democrats.
It wasn't until December's shooting at a Connecticut elementary school left 20 first-graders and six adults dead that gun control rose in prominence. By March, Colorado became the only state outside the Democratic Party's coastal bases to pass sweeping gun control measures, including universal background checks and a ban on high-capacity magazines.
After the Columbine attack, voters closed a loophole that allowed buyers of firearms at gun shows to evade background checks. In the wake of the Aurora massacre, the prospects for more gun control in this libertarian-minded state seemed shaky at best.
Soon after police say a former neuroscience graduate student named James Holmes, armed with a rifle and a high-capacity magazine able to fire 100 bullets, wreaked his carnage, the Democratic lawmaker whose district is home to the Century 16 movie theater where the shooting took place began drafting gun control bills, hoping Coloradans would be more receptive to them.
They weren't. "There was a sense of political fear," recalled state Rep. Rhonda Fields, who became a legislator after her son and his girlfriend were shot to death in 2005 to stop him from testifying at a murder trial.
In a television interview days after the shooting, Democratic Gov. John Hickenlooper appeared to cast doubt on the effectiveness of new gun control laws.
Despite a push by gun control groups and some relatives of those slain in Aurora, moderators at the presidential debates didn't bring up the topic. Craig Hughes, a top adviser to Obama's Colorado campaign, said it felt inappropriate to raise the issue while emotions were so raw. "The right course here was to not politicize it," he said.
Hickenlooper said he had quiet conversations around the state after that and was struck by wide support for universal background checks.
In November, Democrats won both the state House and Senate as Colorado helped re-elect Obama. And on Dec. 12, Hickenlooper declared that "the time is right" to talk about gun control.
Two days later in Connecticut, Adam Lanza, 20, shot and killed his mother, then drove to Sandy Hook Elementary School and opened fire before killing himself. The attack shocked a country that had grown hardened to mass shootings. Obama vowed an all-out push for gun control.
In Colorado, a similar push was already queued up.
New York City Mayor Michael Bloomberg's gun control organization, Mayors Against Illegal Guns, hired four lobbyists to help push gun bills in Colorado. Vice President Joe Biden called state legislators to urge them to vote for the package. Biden told them that Colorado, with its western traditions, could help set the tone for national gun policy.
To Republicans and gun rights groups, the message was clear. "The Obama administration and these East Coast politicians decided that, as Colorado goes, so goes the rest of the nation,'" said GOP state Rep. Mark Waller.
GOP legislators fought furiously to delay the bills' passage. Hundreds of demonstrators circled the state capitol and packed the legislative chambers. Democrats were confident voters were on their side. They have not lost a presidential, gubernatorial or U.S. Senate race for more than a decade, powered by a combination of a growing Hispanic voting population and an influx of coastal moderates.
"The voices that are the loudest (in protest) are not the ones that determine elections here," Laura Chapin, a Democratic strategist who worked for local gun control groups, said after the bills passed.