Correction Appended

Updated: 3:13 p.m.

Having spent more than $70 million to influence the 2010 midterms, American Crossroads announced today that it’s already spent hundreds of thousands of dollars to fight Democrats in 2012.

The conservative outside group has launched radio ads in 12 districts where Democrats narrowly won re-election last month. Crossroads spent $400,000 on the buy, reports spokesman Jonathan Collegio.

The effort is among the first major buys to influence the 2012 cycle and was first reported by Politico. It specifically urges vulnerable Democrats “to demand” a vote on the Bush-era tax cuts.

Collegio provided a script of the radio spots that will run for a full week, unless the tax vote takes place sooner than that. While the ads encourage voters to contact their Congressman, they also link the incumbents to Speaker Nancy Pelosi (D-Calif.), an effective strategy that played out through the 2010 cycle.

“She’s bacccccckkkkk,” says the announcer. “Nancy Pelosi’s at it again — trying to raise taxes while our economy struggles.”

“On New Year’s Day, taxes skyrocket for everyone unless Congress acts. Even low-income families will see their tax rates increase by 50 percent. But Nancy Pelosi is blocking the bipartisan plan to stop these tax hikes. Her reckless ploy could bring back the marriage penalty tax, and hike the death tax on family businesses, farms and savings.”

The spots then name the Democrat in question and ask whether he or she will “side with Nancy Pelosi to raise job-killing taxes, or with struggling families and the small businesses that can create the jobs we need.”

American Crossroads Political Director Carl Forti, appearing at a Monday forum on outside spending, refused to disclose the organization’s specific plans for the next cycle but noted, “We’re going to continue to be active and shape the playing field in 2012.”

American Crossroads and its partner American Crossroads GPS, which was formed this spring, ultimately raised and spent $70 million in the midterm cycle, Forti said. That total, not yet reported by the Federal Election Commission, represents the largest investment by an outside group in 2010 — an investment widely criticized by Democrats because its donors were kept secret.

Forti acknowledged that his group relied heavily on its nonprofit arm, which isn’t required to name the sources of its funding, simply because “some donors didn’t want to be disclosed. … I know they weren’t comfortable.”

He said his group would continue to follow the law, which means the controversial practice is likely to play a significant role in 2012 as well. Forti wouldn’t offer any details about future strategy, but he did not rule out plans to influence the presidential contest.

Those efforts, however, likely wouldn’t involve a crowded GOP primary field.

“It’s difficult to imagine we would ever be involved in a Republican primary,” said Forti, a former communications director at the National Republican Congressional Committee and a former political director for 2008 presidential candidate Mitt Romney.

American Crossroads’ radio spots, meanwhile, are targeting the following Democrats, none of whom earned more than 54 percent of the vote last month: New York Reps. Tim Bishop, Bill Owens and Maurice Hinchey as well as Reps. Gabrielle Giffords (Ariz.), Jim Costa (Calif.), Sanford Bishop (Ga.), Joe Donnelly (Ind.), Ben Chandler (Ky.), Gary Peters (Mich.), Heath Shuler (N.C.), Jason Altmire (Pa.) and Gerry Connolly (Va.).

Democratic Congressional Campaign Committee spokeswoman Jennifer Crider responded to the new ads in a statement.

“After two years of negative, misleading advertising, Karl Rove’s American Crossroads GPS is at it again with more lies funded by secret sources,” Crider said. “Speaker Pelosi and House Democrats are fighting for tax cuts and no amount of false advertising changes that fact.”

Correction: Dec. 15, 2010

The original story misstated the number of districts in which American Crossroads launched radio ads. The group is launching ads in 12 districts.