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Political analysts are already offering predictions of how a slew of presidential hopefuls will fare with Jewish voters in 2008. And as usual, many will be misled into talking about the “Jewish vote” as if it was a political monolith.

While a strong majority of Jews continue to vote Democratic, that fact conceals deep differences within the community. Key among them is the relative weight different factions put on Israel versus domestic affairs.

Political hopefuls of every partisan leaning would do well to keep those differences in mind as they start mining the community today for money, and later for votes.

A Jewish minority makes its political choices based overwhelmingly on Israel and Middle East issues. That group demands agreement on litmus-test issues such as hostility to the Palestinian Authority and the rejection of any “pressure” on Israel to promote U.S. peace plans.

That faction has trended conservative and Republican in recent elections.

Another Jewish minority, this one on the liberal end of the spectrum, is relatively indifferent to the Israel issue. Its votes are based almost entirely on domestic matters or other international issues — this year, the war in Iraq tops the list.

That group is overwhelmingly liberal and Democratic, and rarely ventures into Republican territory.

And then there are Jews in the large, amorphous middle for whom Mideast policy will be an overriding factor only if they see a particular candidate as hostile to Israel’s interests. But given a reasonable comfort level on Israel, these voters will be motivated by other issues, primarily domestic.

This centrist group stuck mostly with Sen. John Kerry (D-Mass.) in 2004, despite the Republican argument that President Bush was the most pro-Israel president ever.

Those divisions will have a big impact on how Jewish voters respond to the many candidates already testing the 2008 presidential waters.

On the Democratic side, Sen. Hillary Clinton (D-N.Y.) provides a case study. After receiving only 54 percent of the Jewish vote in her 2000 Senate win after she unsettled many centrist Jews with her embrace of Yasser Arafat’s wife and statements about the Middle East, she has worked hard to cultivate an image as a consistent pro-Israel hardliner. By most accounts she has succeeded.

But her turn to the right on foreign policy has enraged many liberals in a party inflamed by the Iraq war. With no real competition, that won’t be a problem in her re-election battle this year, but it could loom large if she decides to enter the 2008 presidential primaries.

Potential Democratic contenders such as Clinton, Sen. Joseph Biden of Delaware, former Sen. John Edwards of North Carolina and former Virginia Gov. Mark Warner must find ways to connect with that anti-war Democratic base without looking like they are going too far in the direction of forces that are also hostile to Israel, something that would cut into support from middle-of-the-road Jews.

And Republican strategists will make it harder by tarring every anti-war group as anti-Israel as well.

For Republican hopefuls, the goal right now is to sound more pro-Israel than Prime Minister Ehud Olmert and pretend that domestic issues don’t exist.

The Republican contenders don’t have a lot to lose in terms of votes, but Jewish votes aren’t what they’re after right now; raising funds to mount an effective campaign is particularly important in the early stages, and pro-Israel givers can be a rich vein to mine.

That’s why Republicans who never had much to do with Israel will be donning yarmulkes, talking about peace and security for Israel and bashing Hamas.

But their wooing of Jewish voters will be complicated by other agendas. Sen. John McCain (R-Ariz.) is a case in point.

A few months ago, the maverick senator was widely seen as the Republican with the best chance of attracting Jewish voters.

But to win key GOP primaries, where the Christian right plays a disproportionate role, McCain has to convince that faction he’s one of them — an effort many analysts say is already undercutting his appeal to Jewish swing voters.

Most other likely Republican contenders carry similar baggage.

Potential candidates like Sen. Rick Santorum of Pennsylvania, Kansas Sen. Sam Brownback, Sen. George Allen of Virginia and Sen. Bill Frist of Tennessee would like to pick up more of the Jews in the center by wielding the Israel issue — but that effort will be largely offset by their much stronger need to secure the all-important religious right base.

Democratic and Republican contenders alike face a similar problem: Efforts to reinforce an angry, impatient political base will complicate efforts to attract the Jewish centrists, the community’s real swing voters.

The Democrats start with a huge advantage because most Jews in that group tend to distrust the Republicans on domestic matters, and all the major Democratic candidates have good records on Israel.

But the GOP has an advantage, too: modest expectations. If they can attract new Jewish campaign money and a smattering of Jewish votes in key states, they will count their Jewish outreach efforts a success.

James D. Besser is a Washington correspondent for Jewish newspapers across the country.