WASHINGTON — Talk to veteran campaign watchers about this year’s congressional races, and within seconds they will tell you that they’ve never before seen elections quite like these.

“We’ve never seen a cycle where there’s been this many races this close to an election and you don’t know how it’s going to come out,” said Joy Malkus, the research director at the Chicago-based Joint Action Committee for Political Affairs, or JACPAC, a group that directs funding to candidates who are pro-Israel and moderate on social issues. “And I’ve been doing this since 1982.”

Ben Chouake, president of NORPAC, a New Jersey-based, pro-Israel political action committee, agreed.

“This one has taken twists and turns that surprise almost all of us that follow these events,” he said. “I’ve never seen anything like this in all the years I’ve been doing this — in my lifetime.”

Despite the unfamiliarity of the terrain, the rules of the Jewish fund-raising road remain the same: Stick with your friends and get to know unknowns as fast as possible.

In fact, the only change might be to append a “more-so”: There are many more friends at risk, and there are a lot more unknowns. An anti-incumbent surge already has had an impact in the primaries, ousting a clutch of incumbents in the Senate, where races generally are much more expensive than in the House of Representatives.

“The thing that has created the greatest demand for money in the pro-Israel world are all these open Senate seats,” said Lonny Kaplan, a veteran pro-Israel giver who is based in Philadelphia’s New Jersey suburbs and a past president of the American Israel Public Affairs Committee.

A greater demand and, according to insiders, a surprisingly greater supply considering the economy’s narrow straits. Matt Brooks, who directs the Republican Jewish Coalition, said he has never seen money flowing like this in a non-presidential election year.

“This is the largest effort our leaders have made in a midterm — ever,” he said.

Here are some races to watch in this very watchable season:

Endangered incumbents: The triumvirate

A number of pro-Israel incumbents are at risk in the Senate. Some already have or are almost being written off, among them U.S. Sens. Blanche Lincoln (D-Ark.), Michael Bennet (D-Colo.) and Russ Feingold (D-Wis.).

Others at risk are rallying in the final weeks and have attracted a late burst of pro-Israel attention, including Sens. Harry Reid (D-Nev.), Barbara Boxer (D-Calif.) and Patty Murray (D-Wash.).

Reid, the majority leader, is facing a tough challenge from Sharron Angle, the Tea Party-backed Republican challenger. Reid is considered critical by the pro-Israel community because he has taken the lead in helping to shepherd through Iran sanctions legislation. He’s also seen as having advanced pro-Israel defenses, most recently in a letter with his Republican counterpart, Sen. Mitch McConnel (R-Ky.), pressing President Obama to designate the Turkish group behind the Gaza Strip aid flotilla as terrorist.

If Reid goes, and if the Senate changes hands, its pro-Israel cast is not likely to change: McConnell is also solidly pro-Israel, and Sen. Chuck Schumer (D-N.Y.), perhaps the chamber’s most stalwart Israel defender (and a Jew from Brooklyn), likely would replace Reid.

Yet pro-Israel insiders say it remains a priority to keep in place a party leader who has been a proven champion of Israel.

“I’ve worked very hard for Harry Reid’s campaign, and the pro-Israel community has been very very supportive of him,” Kaplan said. “It’s a very tough race. From my perspective we have a very friendly incumbent — it’s not hard to pick a side there.”

Boxer, a Jewish candidate who is facing former Hewlett Packard CEO Carly Fiorina, is likewise considered important because of the recent trend among liberal Democrats to question Israeli policies.

“She’s very liberal but also a leader,” said a donor who is close to top Democrats and did not want to be further identified. “She puts her name on pro-Israel legislation.”

Getting to know you: the Tea Partiers

Reid’s race is also considered critical also because he is facing Angle, who like most of the candidates backed by the Tea Party movement is friendly to Israel but also seeks budget cuts across the board. That makes her anathema to groups like JACPAC that are concerned about social services.

The Tea Party also makes some pro-Israel conservatives nervous because some in the movement want to slash foreign funding, although they have promised to work out a way to maintain funding for Israel. Some say that reveals a misunderstanding of the holistic nature of foreign aid: If aid is cut across the board, it signals an isolationism that can only harm Israel in the long run even if it benefits from short-term exceptions.

“The pro-Israel community has the challenge of keeping up foreign aid overall” if Tea Party candidates score major successes, said an insider associated with AIPAC.

That effort to keep up foreign aid already is under way, and pro-Israel insiders report warm conversations with Angle in addition to Mike Lee, the Republican candidate in Utah whose Tea Party insurgency unseated longtime incumbent GOP Sen. Bob Bennett, and Ken Buck, who is challenging Colorado’s Bennet.

Other Tea Party candidates have kept their distance from the pro-Israel community. They include Senate hopefuls Joe Miller, a Republican who is leading in Alaska, and Rand Paul in Kentucky.

Paul’s association with his father, U.S. Rep. Ron Paul (R-Texas), whose isolationist polices have resulted in one of the worst pro-Israel records in the House, as well as the younger Paul’s reluctance to parry outside of his inner circle, have conferred upon his opponent, Democrat Jack Conway, the rare status of favored pro-Israel candidate in an open race. The pro-Israel donor community as a rule attempts to split the difference in such races, not wishing to alienate either side.

“Conway has great position papers on all of our issues — Israel, [reproductive] choice and separation of church and state,” JACPAC’s Malkus said. “Rand Paul is not good on any of our issues.”

Unlikely challenges to incumbents — and unlikely incumbent

House Democrats facing challenging races across the country fall into two categories: Those who just months ago were seen as sure bets, and those who beat the odds to win in 2006 and 2008, when Democrats scored victories over a weakened Republican Party. In 2008, those underdog Democrats were buoyed by voters enthusiastic about presidential candidate Barack Obama.

A typical candidate who used to be seen as safe but now is in jeopardy is Rep. Ron Klein (D-Fla.), who defeated his current opponent, Republican Allen West, by 10 points in 2008. Klein has strongly supported Israel in a heavily Jewish district that includes patches of Broward and Palm Beach counties.

West, however, has posed a formidable challenge this time, in part by linking Klein to a president perceived as less friendly to Israel than his predecessors, and in part because of anxieties among retirees over reports that Obama’s health care reform will suck funds from to Medicare, the government-funded insurance plan for retirees. An African-American Iraq war veteran, West also has an Achilles’ heel: Most recently he was associated with a biker gang that does not admit Jews or blacks as members.

Another Florida Jewish congressman is typical of the other column. In 2008, Rep. Alan Grayson (D-Fla.), facing an incumbent weakened by a strong primary challenge, swept in a district that encompasses Orlando and leans Republican.

Grayson, one of the most outspoken critics nationwide of the Republicans, is now in trouble, with outside Republican-affiliated groups pouring money into negative campaign ads. He has offset the blitz by raising four times as much as his Republican opponent, Daniel Webster, in individual donations, stemming from the joy his politically incorrect broadsides bring the Democratic base.

Grayson has accused Republicans of wanting the uninsured to die. Nonpartisan campaign watchers criticized Grayson recently for a TV ad that edited remarks to make Webster appear as if he were endorsing New Testament commands that wives should submit to their husbands. In fact, Webster was advising Christian fathers that they should ignore the commandments in question.

Which pro-Israel are you?

Two major campaigns have split the pro-Israel community: Rep. Mark Kirk (R-Ill.) vs. Alex Giannoulias for the open U.S. Senate seat in Illinois, and Rep. Joe Sestak (D-Pa.) vs. Pat Toomey for the open Senate seat in Pennsylvania.

JACPAC is backing Sestak because of the organization’s twin missions of supporting Israel and moderate social policies. Toomey, Malkus notes, voted against foreign aid more often than not when he was a congressman in the late 1990s and early 2000s.

On the other hand, Sestak has been targeted by right-wing groups like the Emergency Committee for Israel for his associations with the left-wing pro-Israel lobby J Street.

By and large, however, J Street associations have not figured large in the campaign, said Kaplan, who is backing the Democratic incumbent Rush Holt in New Jersey.

JACPAC is staying out of the Kirk-Giannoulias race because of Kirk’s leadership role on pro-Israel issues in the House and his record as a Republican moderate. NORPAC’s Choauake referred to Kirk’s seminal role in shaping the enhanced Iran sanctions legislation that passed over the summer.

“He’s brilliant and hard working; he’s a mover and a shaker, ” he said of Kirk. “He can get stuff done — he knows how to strategize to get to the finish line.”

Races to watch? Try people to watch

Pro-Israel and Jewish money sometimes goes to candidates not because they need it, but because the community sees a future with the person in question.

That’s the case with Kelly Ayotte, a Republican leading in the open race for New Hampshire’s U.S. Senate seat, and Chris Coons, a Democrat in the same position in Delaware.

Ayotte “is someone who’s going to get into the Senate and do well,” Chouake said. “She’s been supported by Democratic and Republican governors as attorney general, which means she must be highly respected. She’s going to be a prime candidate for executive branch if they’re looking for a young Republican woman.”

The same is true of Coons, until now a little-known county executive, said the pro-Israel insider close to Democrats.

“He’s very much up on the issues, very foreign policy attuned,” the insider said. “He  pronounced [Iranian President] Mahmoud Ahmadinejad correctly.”

Asked why he was backing Ayotte in the New Hampshire Senate race instead of Rep. Paul Hodes (D-N.H.), a Jewish congressman with a solid-pro-Israel voting record, NORPAC’S Chouake’s answer was simple: “She called me. He didn’t.”