Just two years removed from being the most powerful voting bloc on Capitol Hill, Blue Dog Democrats are now trying to stave off political extinction.

Rep. Jason Altmire (D-Pa.) is seen through a window as he votes in the Pennsylvania primary election on Tuesday. (Keith Srakocic/AP)

These were the latest blows delivered to the Blue Dogs, whose membership ranks have been decimated the last two years by a perfect political storm that has driven the House Democratic caucus farther to the left than at any time in the last decade.

Rep. Tim Holden (D-Pa.) addresses supporters in this November 2010 file photo. Holden's wife Gwen, left, stands with him. (David McKeown/AP)

Once boasting 54 members in 2010, the Blue Dogs shrank to 26 after those midterm elections scared many into retirement and left many others exposed to political winds that knocked them out that fall. Another pair of retirements last year and early this year, from Jane Harman (Calif.) and Gabrielle Giffords (Ariz.), dropped that total again. Moreover, seven more Blue Dogs have announced their intention to retire at the end of 2012, decided to seek higher office or have lost in their primary race. By the time the 113th Congress is sworn in next January, the Blue Dogs will likely have less than a third of their membership from two years ago.

“It’s back where we started,” Rep. Heath Shuler (D-N.C.), a co-chairman of the coalition, said in an interview Wednesday. He recalled that in 1995 the group was formed with fewer than 20 members, but he said it will be a long slog back to prominence because redistricting has hurt Blue Dogs more than any other group.

Hailing mostly from rural to exurban districts, Blue Dogs were left vulnerable in states where GOP governors and legislatures drew the lines. Altmire was thrown into a western Pennsylvania district with Rep. Mark A. Critz (D), a former aide to the late Democratic hero John P. Murtha, whose former union backers supported Critz after Altmire twice opposed President Obama’s health-care law.

Holden, who represented a swing district for 20 years and defeated a veteran Republican 10 years ago after redistricting, had a unique problem: His new district became too Democratic, particularly because Holden also opposed the health-care bill. Republicans in Harrisburg dumped Democratic voters from GOP seats into the new Holden district around Reading. Then came a liberal challenge in the form of attorney Matt Cartwright, who won roughly 60 percent of the vote in a rout of Holden.

Other House Democrats have taken notice of the diminished Blue Dog status. “That is a concern that we have in the caucus, and will continue to have,” Rep. John Larson (D-Conn.), chairman of the House Democratic Caucus who regularly hangs out with Holden and Altmire in what is known as “Pennsylvania Corner” in the chamber, told reporters Wednesday.

It’s an amazing turn of events. Little more than two years ago they were the final focus of Obama and then-Speaker Nancy Pelosi (D-Calif.) as they tried to round up votes for the health-care bill. Altmire became a bellewether, so much so that the Washington Post ran a five-column photo of him over an A1 story about his deliberations. He opposed the legislation, but enough Blue Dogs supported the law to boost its passage, a refrain that played out on every big vote the first two years of Obama’s presidency.

The group's long-term prospects are endangered on a few other political and demographic fronts. This moderate group has lost almost all of its female members, down to just Rep. Loretta Sanchez (D-Calif.), whose Orange County district often makes her more in line with the suburban New Democrat Coalition than the rural-tilting Blue Dogs.

In addition, the Blue Dogs have had a terrible track record of promoting their own members into the Senate or governor’s mansions: While more than Senate Democrats 15 previously served in the House, Sen. Kirsten Gillibrand (D-N.Y.) is the only former Blue Dog in the Senate, and she has cut a decidedly more liberal profile since arriving in the so-called upper chamber in 2009. No governors served as Blue Dogs in the House. The coalition lacks a political godfather who can carry the torch in a more prominent post, which would help with recruiting and fundraising.

Interviews with a handful of current and former senior aides to Blue Dogs all focused on recruiting, with each strategist suggesting that finding the right candidates in these regions can be very painstaking but also very rewarding. When he served as the Democratic Congressional Campaign Committee chairman in 2006, then-Rep. Rahm Emanuel (D-Ill.) found non-politicians such as Shuler — a college football legend in the South who played a few years in the NFL — and telegenic sheriff Brad Ellsworth in Evansville, Ind., to run in very conservative districts.

They both won and helped propel the Democrats into the majority for the first time in 12 years, giving Pelosi her historic speakership.

Privately, many Blue Dogs and their staff blame Pelosi’s liberal leadership. Her image was run countless times in 2010 against Shuler and Altmire, both of whom were rare survivors. Despite a coordinated recruiting effort by the DCCC this time around, few Blue Dogs who lost in 2010 have opted to run for their old seat. Shuler and Rep. Mike Ross (D-Ark.), both co-chairmen of the coalition, decided to retire at the end of this year rather than run for re-election in new districts that tilted toward Republicans. Ellsworth lost a Senate race in 2010 by 15 percentage points, leaving behind a House seat that flipped to Republicans.

Shuler, who spent time Wednesday on a conference call trying to recruit Blue Dog candidates, said his coalition resonates with most voters in terms of its anti-deficit message but is struggling with translating that into seats in Congress. “The Blue Dogs represent 80 percent of America, but there are just 25 of us in the House,” he said.