JTA's Ron Kampeas reports on the brouhaha developing in Pennsylvania between Democratic Senate candidate Joe Sestak and the Emergency Committee for Israel:

A close battle for Pennsylvania's open U.S. Senate seat is quickly turning into a proxy war between self-described pro-Israel forces on the left and right. The immediate fight is over the pro-Israel credentials of U.S. Rep. Joe Sestak (D-Pa.), who knocked off the incumbent Arlen Specter in the Democratic primary and is now facing Republican former congressman Pat Toomey. The Emergency Committee for Israel, a group recently founded by neoconservatives and evangelical Christians, released a TV ad last week attacking Sestak and questioning whether he understands "Israel is America's ally." J Street countered this week with an ad defending Sestak and urging viewers to tell him to “keep fighting for peace and security in the Middle East." Both ads are running in Philadelphia markets and on cable. For J Street the campaign is turning into a test of whether the organization, which backs U.S. pressure on Israel and the Palestinians in pursuit of a two-sate solution, can break through and insulate candidates from attacks launched by centrist and right-wing segments of the pro-Israel community. Meanwhile, with neoconservative scion William Kristol calling it the "pro-Israel wing of the pro-Israel community," the Emergency Committee for Israel sees the race as a first step in convincing Jewish voters to break with President Obama’s Middle East policy and candidates who support it. The organization is clearly primed to take shots at candidates like Sestak, 58, who insist their support for Obama, even when he pressures Israel, is pro-Israel. The race will be closely watched throughout the country: A number of Congress members with known dovish tendencies have declined J Street's support until now for fear of alienating the American Israel Public Affairs Committee and its backers. One prominent example is Rep. Adam Schiff (D-Calif.), a Jewish lawmaker who took J Street's money in 2008 but is not on their roster of 61 endorsees this year. In an interview with The New York Jewish Week, Gary Bauer, the evangelical Christian leader and onetime hopeful for the Republican presidential nomination, called Sestak "a perfect example of an elected official running for higher office who uses these rote, throwaway phrases about being pro-Israel, but who has developed a pretty consistent record of associating with organizations and individuals who are anything but."