From The New York Times
The defeat of two conservative House Democrats by more liberal opponents in Tuesday’s Pennsylvania primary illustrates the strong hold the new health care law
still has over committed Democratic voters and foreshadows an even more polarized Congress next year in the aftermath of the latest round of redistricting.
Representatives Jason Altmire and Tim Holden both lost in primaries to opponents who joined together with activist groups to pummel the veteran lawmakers over the opposition to the new health care law and climate change legislation
— positions they had used to their advantage in the past to show their independence from President Obama and the Democratic Party.
“A lot of us thought of his record as his strength,” said Hugh M. Reiley, the chairman of the Schuylkill County Democratic Party, referring to Mr. Holden. “He was not falling prey to all that party bickering. He was able to reach across the aisle.”
“Last night, the Democratic Party became more liberal,” he added.
While Republicans have seized on the health care law as a political weapon to employ against the president and Congressional Democrats, many Democratic voters and party activists see it as a major achievement and are poised to punish Democrats who fought it. The results on Tuesday also suggest health care could be a major rallying cry if the Supreme Court overturns all or part of the law this summer.
In eastern Pennsylvania, state Republicans stuffed the Democratic cities of Scranton and Wilkes-Barre into Mr. Holden’s formerly conservative-leaning seat. The result: A 10-term congressman and founding member of the centrist Blue Dog coalition was trounced by a newcomer, Matt Cartwright, a Scranton lawyer who ran hard against Mr. Holden’s moderate voting record.
The ouster of the Democratic incumbents — and the tough primaries being waged against some House Republicans — suggest that redistricting ultimately is going to send more liberal Democrats and more conservative Republicans to the House.
The parties have become more polarized in recent decades, several academic studies have found. The demise of the conservative “Dixiecrats” in the 1960s and ’70s made the Democratic Party more liberal, and Republicans have moved even further to the right than Democrats have moved to the left, the studies show. Elections like Tuesday’s suggest Democrats may be taking the Republicans’ cue, driven by the same activist forces that pushed them rightward.
“In civics class in high school, you learn there are 435 members of Congress, and every one of them could lose in the next election. Now we’re down to less than 100 who can ever get beat in a general election,” lamented Representative Mike Ross of Arkansas, a Blue Dog co-chairman who is retiring from Congress this year. “So the Democrats run to their corner. The Republicans run to their corner, and as a result the country is being run by the extremes.”
“Redistricting,” he added, “has been bad for the country.”
And from The Washington Post
is an article entitled "Blue Dog Democrats trying to stave off extinction following Pennsylvania losses":
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.
It’s increasingly unclear whether Democrats can ever reclaim the House majority unless they pick up ground in the conservative-leaning terrain that the Blue Dogs once represented. In addition, with so few moderates left, there are fewer House members in the political center to create the sort of bipartisan coalition that in the past has provided the bulwark of support for budget compromises.
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.