After 30 years in politics, Pennsylvania Senator Arlen Specter's career ended Tuesday night when Rep. Joe Sestak defeated him in the Democratic senatorial primary. Specter had drawn fire from the right in 2009 when he switched parties, but received extensive White House aid for his failed reelection bid. What lessons should we draw from his defeat?

• Dems Must Learn to Champion Anti-Incumbent Frustration  The New York Times' Jeff Zeleny and Carl Hulse say the vote "illustrated anew the serious threats both parties face from candidates who are able to portray themselves as outsiders and eager to shake up the system." Neither the White House nor organized labor could save Specter. "The results were sobering for both parties, amounting to a rejection of candidates selected and backed by leaders in Washington who found themselves out of step with their electorates."

• Grassroots and Parties Out of Touch  ABC News' Rick Klein asserts, "The primary results confirm that both parties have not only lost touch with their grass-roots, they’ve watched them turn into thickets that can entangle even the most experienced tenders of electoral gardens. Those weeds don’t respect property lines labeled 'D' and 'R.'" However, "Joe Sestak’s victory leaves Democrats with a roughly equal chance of holding on to the seat in Pennsylvania."

• The White House Is on Defensive  The Washington Post's Dan Balz and Chris Cillizza write, "Democrats remain on the defensive heading toward November, in large part because of divisions over Obama's agenda, the high jobless rate and the size of the federal budget deficit." The Pennsylvania race pitted the White House against Democratic activists and the Arkansas race pitted the White House against organized labor.

• Did Obama's 'Change' Call Backfire?  The Wall Street Journal's Gerald Seib warns, "Barack Obama discovered in 2008 that 'change' was the most powerful word in American politics. It still is—and there's no reason to think its potency will dissipate between now and November's congressional elections. ... All that suggests that President Obama didn't catch the national change wave at its crest, as many thought at the time, but rather jumped on it only as it was gathering strength. In some ways, all that has changed are the issues fueling the public's desire to change the political makeup of their capital."

• He 'Surrendered' His 'Power'  National Review's Kathryn Jean Lopez sighs, "As much as Arlen Specter has driven me batty over the years, he was long a powerful senator whom everyone wanted on his side. (And when he was on your side, you sometimes worried he wouldn't be for long, or enough!) He was respected and feared. He was frustrating. But Arlen Specter surrendered the power he built for himself — and his state — when he handed his reputation over to Barack Obama. It’s a shame to see a career end like that."

• Democrats Don't Like Clinton Impeachers  Slate's Jon Dickerson shrugs, "it was hard for a senator who spent almost five terms as a Republican to reinvent himself as a Democrat." Dickerson cites Specter's second book, titled "Passion for Truth" and subtitled "Impeaching Clinton." Liberal Pennsylvania blogger Duncan Black's reaction bears that theory out:

There are a lot of reasons Arlen managed to work his fake moderate game for so long, but I'm glad that era is over. I hope (and am mildly optimistic) that Joe Sestak will be a better senator than one might expect, but in any case getting rid of Arlen was a worthy goal in and of itself.

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