Three days after a gunman calling himself the Joker from the Batman series shot 12 people dead in a suburban Denver movie theater, the National Rifle Association sent out a letter asking for money.

“The future of your Second Amendment rights will be at stake,” the letter said. “And nothing less than the future of our country and our freedom will be at stake.”

Additional Photos

Police Chief John Wilson holds a confiscated semiautomatic weapon at the police station’s evidence room in Montgomery, Ala. An NRA solicitation letter warns that the re-election of President Obama could potentially lead to a “ban on semiautomatic weapons.” 2004 File Photo/The Associated Press

The letter dated July 23, sent to NRA supporters in Colorado and other states, doesn’t mention the gunfire during the July 20 showing of the new Batman movie in Aurora, Colo.

It was also sent as the national debate over gun rights has flared up, prompted by the Aurora shooting and continuing after Sunday’s shootings at a Sikh temple near Milwaukee. A gunman identified as Wade Michael Page, 40, an Army veteran, is suspected of killing six people in that incident before police shot him dead.

The four-page solicitation from NRA Executive Vice President Wayne LaPierre was sent to drum up funds to underwrite an advertising and grass-roots campaign to defeat President Obama and elect gun-rights supporters in Congress.

The letter was “very insensitive,” said Eileen McCarron, president of the Colorado Ceasefire Capitol Fund, a gun-control advocacy group.

“Couldn’t they have waited at least a week, especially here? People’s souls are really wounded,” she said.

A copy of the NRA solicitation was provided by a Republican former U.S. lawmaker who asked not to be identified as a condition for releasing the letter. The NRA public affairs office didn’t return phone calls seeking comment on the fundraising letter.

The group has publicly been silent on gun-control proposals since the Colorado shooting. In response to the Wisconsin killings, Andrew Arulanandam, the NRA’s spokesman, issued this statement: “NRA joins all Americans in extending our heartfelt condolences to the victims, their families and the community affected by this tragedy. We will not have further comment until all the facts are known.”

Fundraising is increasingly important to the NRA, based in Fairfax, Va. The gun-rights group’s membership dues were 44 percent of its income in 2010, down from 58 percent in 2008. In that period, gifts, grants and other contributions rose to 26 percent from 16 percent of revenue, according to the group’s tax returns. Total income was $228 million in 2010, compared with $248 million in 2008.

The NRA’s political action committee raised almost $10 million from January 2011 through June 30, 2012, to spend on election campaigns, about two-thirds of what it collected in 2007 and 2008, according to the Washington-based Center for Responsive Politics. It has spent $18.9 million on federal campaigns since 1989, which ranks it as the 46th biggest donor in that period, according to the center, a nonpartisan group that tracks money in politics.

The solicitation letter says that Obama’s re-election would result in the “confiscation of our firearms” and potentially a “ban on semi-automatic weapons.” James Holmes, 24, the suspect in the Aurora killings, had four semi-automatic weapons at the theater, police said.

The letter says the money will be used for “hundreds of thousands” of TV and radio ads, “especially in a handful of key swing states.” The group also plans to buy ads in newspapers and on the Internet and send mail to “millions” of gun owners, LaPierre wrote in the letter.

The “extremist rhetoric” that LaPierre uses in the letter would offend the “mainstream public” in the days after the Colorado shooting, said Dan Gross, president of the Washington-based Brady Center to Prevent Gun Violence, a gun-control advocacy group.

“They know the public wants answers and solutions to a problem that Aurora is one tragic example of,” Gross said. “So this kind of rhetoric isn’t going to fly, but it’s just the kind of rhetoric that helps them raise money behind the scenes with a small group of extremists.”

Colorado State Shooting Association President Tony Fabian said criticism of the fundraising letter was misplaced and that the letter was probably in the works well before the Colorado shooting.

“These fundraising strategies require a lot of months of planning and scheduling,” Fabian said. “It looks like the timing is purely a coincidence.”

The NRA’s fundraising has benefited from a provision in a 1986 law that lifted the ban on interstate sales of ammunition to consumers, allowing for mail-order purchases and then Internet sales. At the time the NRA praised the law as the “greatest legislative milestone.”

Via donations attached to mail-order and online sales, the NRA has collected $9.3 million since 1992, according to the website of MidwayUSA, a Columbia, Mo., ammunition dealer.

The Colorado mass shooting, in which police say Holmes bought 6,000 rounds of ammunition on the Internet, has prompted calls for legislation to limit mail-order sales of guns and ammunition. Former U.S. Rep. James Oberstar, D-Minn., who backed the gun law in 1986, now says allowing mail-order sales may have been a mistake.

The donations coming from mail-order and online purchases demonstrate why the NRA is reluctant to join the debate on new gun regulations, said Josh Sugarmann, head of the Violence Policy Center, a Washington-based gun-control advocacy group.

“Recognizing the NRA’s financial stake and its main benefactor have on online sales, it’s guaranteed they will oppose any changes,” Sugarmann said.

The NRA fundraising letter says the presidential election will have major consequences.

“The night of November 6, 2012, you and I will lose more on the election battlefield than our nation has lost in any battle, anytime, anywhere,” LaPierre wrote. “Or, we will win our greatest victory as NRA members and freedom-loving Americans.”

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