Updated: 11:37 a.m.

As the House campaign committees struggle to emerge from suffocating debt, the independent conservative group Crossroads GPS is up this week with its second significant ad buy this cycle.

This one — radio buys totaling $450,000 across nearly two dozen districts — aims to both attack vulnerable Democrats and tie them to President Barack Obama and Minority Leader Nancy Pelosi (D-Calif.) while supporting Republicans in swing districts.

“Last week, Members of Congress like Joe Donnelly voted to continue the failed spending policies of Pelosi and Obama. They just don’t get it,” says the narrator in a sample of a $15,735 buy running this week in Indiana’s 2nd district, where Donnelly squeaked out a victory of less than 2 points last fall. “Call Congressman Donnelly. Tell him that voting against budget cuts doesn’t cut it. Tell him to stop the spending now to make America great again.”

Overall, Crossroads is launching similar ads in 22 districts, targeting Democrats in 12 districts and supporting Republicans in another 10.

The full breakdown, as reported first this morning by the Washington Post, includes Democratic Reps. Jim Costa (Calif.), Leonard Boswell (Iowa), Ben Chandler (Ky.), Tim Walz (Minn.), Martin Heinrich (N.M.), Tim Bishop (N.Y.), Bill Owens (N.Y.), Mark Critz (Pa.), Jim Matheson (Utah), Mike Michaud (Maine) and Rick Larsen (Wash.).

The Republicans getting some help from Crossroads include potentially vulnerable Reps. Bob Dold (Ill.), Chip Cravaack (Minn.), Jon Runyan (N.J.), Robert Hurt (Va.), Sean Duffy (Wis.), David McKinley (W.Va.), Quico Canseco (Texas), Jamie Herrera Beutler (Wash.), Lou Barletta (Pa.) and Frank Guinta (N.H.). All of the Republicans are freshmen.

Earlier in the month, Crossroads launched a $95,000 buy to defend Republicans in 19 districts where the Democratic Congressional Campaign Committee, which finished the 2010 cycle with almost $20 million in debt, had earlier launched far more modestly-priced attacks.

Crossroads, which is registered as a non-profit organization that does not need to disclose its donors, raised and spent more than $70 million in the last cycle, has no known debt and is already proving that it will be a major player in the 2012 cycle, especially at a time when the DCCC and the National Republican Congressional Committee are struggling to pay off combined debts of almost $30 million.

The financial difficulties could help explain why the NRCC wouldn’t disclose the cost of plans, also published this morning by the Washington Post, to launch a series of phone calls targeting 10 vulnerable Democrats for their opposition to the House GOP’s sweeping budget cuts.

The NRCC tells Roll Call that its decision not to disclose the size of the buy has nothing to do with its $10.5 million debt. The DCCC debt totals $18.6 million.

“We just never give out the dollar amount,” NRCC spokeswoman Joanna Burgos said. “Our debt is manageable and we have a plan to pay it off, unlike the Democrats.”

Matheson, Chandler, Donnelly, Bishop and Heinrich are being targeted by both the Crossroads ads and the NRCC calls. Other Democrats who are getting calls in their districts are Reps. Mike McIntyre (N.C.), Jason Altmire (Pa.), Larry Kissell (N.C.), Dan Boren (Okla.) and Nick Rahall (W.Va.).