Gun sales in Colorado have soared in the aftermath of the shooting tragedy in Aurora that claimed 12 lives and left 58 wounded, the Denver Post reported Tuesday.

Background checks carried out on customers as they buy guns were up 41 percent in the wake of Friday's shooting at a packed cinema in the Colorado town, the newspaper reported.

There was also a spike in people seeking training for a concealed carry permit, the report said. Carrying a handgun or other weapon in public in a concealed manner is legal with a permit in 49 of the 50 US states. Illinois is the only state without such a provision.

"It's been insane," Jake Meyers, an employee at Rocky Mountain Guns and Ammo in the town of Parker, told the newspaper, saying there were 15 to 20 people waiting outside the store when he arrived for work just hours after the shooting.

"A lot of it is people saying, 'I didn't think I needed a gun, but now I do,'" Meyers was quoted as saying. "When it happens in your backyard, people start reassessing -- 'Hey, I go to the movies.'"

Colorado approved 2,887 background checks Friday through Sunday, a 43 percent rise over the previous week and a 39 percent increase over the same period last year, according to the report, which reported 41 percent overall as its headline figure.

Calls for a re-examination of America's gun laws mounted in the aftermath of the tragedy as it emerged that the suspected Aurora shooter, James Holmes, bought his four weapons legally.

Over eight weeks, he stocked up on the Internet on 6,300 rounds of ammunition: 3,000 for his .233 semi-automatic AR-15 rifle, another 3,000 for his two Glock pistols and 300 cartridges for his pump-action shotgun.

Holmes, a 24-year-old graduate student, also bought a special magazine for his military-style assault rifle that enabled him to fire up to 50 to 60 rounds per minute.

Despite profound soul-searching over the Colorado shooting rampage, there is no political willingness to end the long stalemate over the toxic gun law issue, particularly in a US election year.

Several key battlegrounds in November's elections -- Ohio, Pennsylvania and Virginia, for example -- have gun-friendly populations that remain wedded to their right to bear arms, which is enshrined in the US Constitution.