Salena Zito

In 2010, Pennsylvania will have hot races for governor and the U.S. Senate, too. Add the seat left by Republican U.S. Rep. Jim Gerlach in the Southeast – a close race that will have tons of money from both parties – and you have Pennsylvania once again at the epicenter of national politics.

Right now, the state’s biggest buzz is the “Joe-mentum” radiating from the declared but unfiled U.S. Senate candidacy of Rep. Joe Sestak, a Delaware County Democrat who is taking on the 28-year incumbent and newly-declared Democrat, Arlen Specter.

When Specter switched parties this spring, he bargained for (and got) the field cleared by President Barack Obama and Gov. Ed Rendell, first with their endorsements and then with their mandates that party members follow suit.

What they did not count on was the tenacity, persistence and appeal of Sestak, who refused to clear a path for Specter, or the tepid response from committee members and party chairs to the long-time Republican Specter.

“Leadership can only make endorsements, and while it is good to know where they stand, that does not mean we have to fall in line,” says Jim Burn, the Democrats’ Allegheny County chairman.

Villanova University’s Lara Brown strongly believes Sestak can beat Specter in the primary: “The only caveat is that he needs to continue raising substantial sums of money, so that he can buy the advertising time.”

That cash also will allow him to do other marketing, such as mail pieces and maybe billboards, to help him become better-known outside of Philly and her suburbs.

Sestak has significant structural advantages that likely were part of his decision-making.

First, Pennsylvania has a closed primary. This is incredibly important, because liberal Republicans (and Republican-leaning independents registered with the GOP) may have been inclined to stick with Specter but cannot vote for him against Sestak – unless they change their party registration.

While some may do so, it is doubtful enough will to change the outcome. Most will want to remain registered Republican, to vote in the party's gubernatorial and Senate primaries.

Unlike last year’s presidential primary, when some party-switching occurred, a few exciting races will be on the GOP side next year, Brown says. Besides, few Republicans will feel that committed to Specter, who abandoned their party and was disloyal on numerous votes before that.

Salena Zito

Salena Zito is a political analyst, reporter and columnist.