The following Op-Ed was written by Tevi troy for Politico:

For decades, conservative Jews have been wondering when the traditionally Democratic Jewish voter would make the same migration as other ethnic groups and start voting Republican. At the same time, liberal Jews have been explaining the variety of historical and religious reasons why such a switch would never take place.

While this debate seems never-ending, it’s possible that both sides have been looking at the wrong metrics. The shift in the Jewish vote is already taking place — but at the state, not the national level.

Nationally, Jews are only about 2 percent of the U.S. population, but they are heavily represented in big cities and have disproportionately high voter turnout rates. They are major contributors to both parties, though Democrats get the lion’s share. Some groups within the Jewish community, like Orthodox Jews, have shifted to the GOP – 70 percent supported George W. Bush in 2004. In addition, Jewish neoconservatives have long been vocal Republicans — with voices louder than their numbers suggest. Overall, though, the Jewish vote remains strongly Democratic at the national level. The GOP share in the last two decades fluctuating between Bush’s 25 percent in 2004 and his father’s 11 percent in 1992.

At the state level, however, Jews can and do vote less Democratic. New Jersey Gov. Chris Christie attracted 38 percent of the Jewish vote in 2009, proving that Republicans who can be competitive in the Jewish community gain an edge against Democratic opponents, who then can’t take the Jewish vote for granted.

For this reason, it is worth paying close attention to the Jewish vote in close Senate races in states with significant Jewish populations. In the complicated Pennsylvania race, for example, a Republican-turned-Democrat Jewish senator, Arlen Specter, is involuntarily leaving, and the Jewish vote is likely to help determine his successor.

James Carville famously described Pennsylvania as “Philadelphia on one end, Pittsburgh on the other, with Alabama in the middle.” Many Jewish voters may be joining the Alabama contingent in this election because the Democratic nominee, Joe Sestak, signed the “Gaza 54 letter,” which called for Washington to pressure Israel to end the Gaza blockade.

Commentary blogger Jennifer Rubin described Sestak as having a “tough love” approach toward Israel: “There is toughness but no love of the Jewish state here.” Jewish unhappiness with Sestak has been helping the pro-Israel Republican Pat Toomey. The race is very close.

In Florida, the dynamics are even more complicated, making the Jewish vote even more important. Former Republican-turned-independent Charlie Crist recently spoke to a Jewish audience at Boca Raton’s Temple Beth Shalom, pointing to his wife, Carole, and saying, “She’s a nice Jewish girl — I married up.”

Crist also secured the strong endorsement of Jewish former Democratic Rep. Robert Wexler. If Crist just splits the traditionally Democratic Jewish vote with the Democratic candidate Kendrick Meek, that could be a boost for the GOP candidate Marco Rubio.

Jewish voters are also important in New Jersey’s 12th district, where Scott Sipprelle is challenging Rush Holt – another Gaza 54 letter signer. Neither is Jewish, but a “Rabbis for Sipprelle” group is seeking to raise awareness of Holt’s action in the Jewish community. These votes could help bring the district back to the Republicans. The GOP had held it for three decades before Holt won the seat in 1998 – supported in part by an influx of New York Jewish retirees.

This election year could be consequential for another reason as well. The tide is turning against some elected Democrats who have Jewish roots, which has long been a source of Jewish pride and voter identification. In addition to Specter, who lost the Democratic primary, other Jewish Democratic senators who could lose seats this year include Russ Feingold of Wisconsin, Colorado’s Michael Bennet (whose mother was Jewish, but does not self-identify that way) and perhaps Barbara Boxer of California.

In contrast, a number of rising GOP Jewish stars could gain in November. House Minority Whip Eric Cantor could get a big promotion if Republicans take back the House. There are at least nine additional Jewish Republicans running for office across the nation, including former Marine Josh Mandel, who is running a strong campaign for Ohio state treasurer.

Another Jewish Republican, Harvard Law grad Joel Pollak, won the endorsement of well-known Democrat, and Harvard Law professor, Alan Dershowitz. Pollak is running against Jan Schakowsky (also Jewish) in the heavily Jewish – and traditionally Democratic – 9th district of Illinois.

One reason for the apparent fluidity of the Jewish vote could be President Barack Obama’s perceived tough stance on Israel, as compared to some of his predecessors. According to an American Jewish Committee poll this spring, Obama’s approval rating is now 57 percent among Jews, a significant drop from the 78 percent who supported him in 2008.

Israel, however, is not the only factor that drives the Jewish vote. Jewish voters, like other voters, are worried about the economy, the deficit, and health care, and these issues increase in importance in the state and local elections that take place in an off-year election. In the aggregate and in national elections, the Jewish vote appears likely to remain Democratic for the foreseeable future. But Jewish voters in state elections across the country could significantly change our political landscape in November.

Tevi Troy is a visiting senior fellow at the Hudson Institute. A former senior White House aide and deputy secretary of Health and Human Services in the Bush administration, he also served as the White House Jewish Liaison.

(Tevi Troy is a visiting senior fellow at the Hudson Institute. A former senior White House aide and deputy secretary of Health and Human Services in the Bush administration, he also served as the White House Jewish Liaison.)