By Louis Jacobson

PoliticsPA Contributing Writer

As a state that has been home to more competitive congressional races this year than any other state, Pennsylvania has been one of the most crucial targets for Republican strategists looking to take over the House. And on Election Day, the Keystone State did not disappoint: Almost everything that could have gone the GOP’s way, did.

The GOP flipped five seats – those held by Democratic Reps. Chris Carney, Kathy Dahlkemper, Paul Kanjorski and Patrick Murphy – plus the open seat being vacated by the night’s losing Senate candidate, Democrat Joe Sestak.

In these losses, two factors stand out.

One is how consistently solid the Republican victories were. According to unofficial results as of early Wednesday morning, not one of the Democratic nominees in these five districts exceeded 46 percent of the vote.

Even more striking was the diversity of the four incumbents who lost.

Kanjorski was a long-tenured “old bull” with important committee influence in Washington; Carney, Dahlkemper and Murphy were all younger members elected in the past four years.

The four districts the Democrats lost were spread widely across the state, from the northeast (Carney and Kanjorski) to the southeast (Murphy) to the northwest (Dahlkemper). They ranged from moderate suburban territory (Murphy’s Bucks County) to aging industrial regions (each of the other three).

And the four losing incumbents ranged from anti-abortion lawmakers (Dahlkemper) to one of the House’s leading advocates for ending the military’s Don’t Ask, Don’t Tell policy (Murphy).

Meanwhile, the Democrats were unable to seize the two opportunities they had to oust potentially vulnerable GOP incumbents.

Despite being a strong recruit, Democrat John Callahan failed to break 40 percent against GOP Rep. Charlie Dent in a swing Lehigh Valley district, while Democratic newcomer Manan Trivedi took only 43 percent against GOP Rep. Jim Gerlach, who represents a Democratic-leaning district in southeastern Pennsylvania.

The bottom line is that the U.S. House victories by the GOP were broad-based by almost any measure. And they more than carried the state’s weight in helping flip the House as a whole.

There were some silver linings for the Democrats.

Three vulnerable Democratic incumbents survived – though two of them were close calls.

Rep. Jason Altmire, who represents a blue-collar district stretching north of Pittsburgh, defeated a little-known Republican, Keith Rothfus, by the slimmest of margins—51 percent-49 percent.

Rep. Mark Critz, the former aide to the late Democratic Rep. John Murtha who won a special election to represent the district earlier this year, held on by the same 51 percent-49 percent margin as Altmire. Critz defeated Tim Burns, the Republican he had defeated by a notably wider margin just a few months earlier.

The final vulnerable Democratic district in the state had become less vulnerable as the year progressed, and in fact it ended up being the only relatively comfortable Democratic victory of the bunch. Rep. Tim Holden, who represents a GOP-leaning district in central Pennsylvania, defeated Republican Dave Argall, 56 percent-44 percent.

Something that tied together these three Democrats – and may have enabled their victories – was that none of them voted for the Democratic health care bill. Altmire and Holden voted no, while Critz wasn’t in Congress at the time.

One final, purely self-promotional note: As many of our readers know, we’ve rated the most vulnerable U.S. House seats in Pennsylvania for most of this year. The list shifted here and there over the course of the year, but the top five seats in our final rankings all flipped. The bottom five seats did not.