WASHINGTON (CNN) -- Twelve survivors of the shooting that gravely wounded former Rep. Gabrielle Giffords and killed six others met Wednesday with Attorney General Eric Holder to seek his support for stricter enforcement of gun sale checks and tighter requirements on gun sales.

The group of survivors from the Tucson, Arizona, shooting is working with New York Mayor Michael Bloomberg and others with Mayors Against Illegal Guns to combat gun violence.

Ken Dorushka, one of the survivors, said Holder "seemed to be very supportive of what we're trying to do."

The Arizona contingent hopes to get President Obama and Gov. Mitt Romney to present plans for ending gun violence. Neither party has wanted to discuss gun violence during the campaign. Dorushka acknowledged the National Rifle Association has enormous political clout, and his group faces an uphill task.

The Justice Department confirmed the attorney general met with the group for about an hour, but would not discuss what was talked about. The Arizona delegation submitted to Holder hundreds of thousands of signatures in support of the campaign.

"The meeting was positive and constructive," said Holder spokeswoman Tracy Schmaler.

The group of survivors who met with Holder did not include Giffords, but did include Roxanna Green, the mother of 9-year-old Christina-Taylor Green who was killed in the January 8, 2011, shooting spree. Jared Lee Loughner has pleaded guilty in the shooting.

Also among the survivors in the delegation was Bill Badger, who like Giffords was shot in the head. Badger was able to knock Loughner to the ground and helped hold him down until police arrived.

The group supports the Fix Gun Check program pushed by Sen. Charles Schumer of New York. The program calls for closing the "gun show loophole," which gun control advocates have long demanded. Dorushka said an estimated 40% of gun sales occur at gun shows, flea markets and backyard sales, where unlicensed gun dealers are not required to perform background checks on prospective purchasers.

Giffords continues a slow recovery at home. She resigned her congressional seat on July 25. Loughner pleaded guilty in a deal with federal prosecutors to 19 counts of murder and attempted murder. He will not receive the death penalty, but is expected to serve life in prison after he is formally sentenced on November 15.