The lobbying powerhouse's conference, to be held June 2-4, is the only policy event since the presidential election campaign was launched that has attracted all three major candidates: U.S. Sens. Barack Obama (D-Ill.), Hillary Rodham Clinton (D-N.Y.) and John McCain (R-Ariz.).
The conference comes on the heels of a spate of Middle East-related dust-ups involving Obama and McCain.
They have engaged in a bruising battle over Iran policy. McCain favors increased isolation for Iran, Obama favors what he calls tough diplomacy and direct negotiations, and both are casting their arguments in terms of what's better for Israel.
Those differences promise a lively conference. That's fine, officials of the American Israel Public Affairs Committee said.
"They want to compete over who's more pro-Israel?" one said. "Let them compete."
Few holds have been barred in the fierce competition. McCain has supported President Bush's contention before the Knesset earlier this month that directly dealing with Iran amounts to Nazi-era appeasement. Some administration aides described the remarks as a swipe at Obama's position.
Democrats counter that what they call the "Bush-McCain" policy of not dealing with Iran has "made matters worse" for Israel, in the words of U.S. Rep. Nancy Pelosi (D-Calif.), the speaker of the House of Representatives.
In addition, McCain and his surrogates have sought to score points by highlighting the fact that a Hamas official publicly praised Obama. The Democratic front-runner called such talk a "smear," noting that he and McCain hold virtually identical positions on isolating the Palestinian terrorist group.
The candidates are unlikely to tamp things down in time for next week.
"Senator Obama will continue to describe his strong support for Israel's security and the U.S.-Israel relationship, and his concern about how Israel's security has not been enhanced by the current administration's policies, and how his policies will advance U.S. national security interests and also Israel's security," said a senior aide to the candidate who asked not to be named.
Ann Lewis, a senior Clinton adviser, said, "This is like the Super Bowl for those of us who care about Israel and foreign policy. For Hillary it's like having a conversation with old friends. There are so many people who will be at this meeting that she has known, that she has worked with, some of her best friends. She looks forward to it."
Lewis did not have details of Clinton's AIPAC speech, but said the candidate would likely emphasize her deep ties with the pro-Israel community.
"It will be very much about her commitment and her record, from Magen David Adom to the anti-Semitic language in the textbooks, to going to Israel and seeing the victims of terrorism in the hospitals," she said.
Clinton was behind legislation that helped shepherd the Israeli first responder into the International Red Cross umbrella, and also backs tough scrutiny of Palestinian textbooks. Equally important, Lewis said, "would be the dangers posed by Iran."
The McCain campaign did not respond in time for publication, but it seemed clear he also would not stint.
In a nuclear policy speech Tuesday in Denver, McCain subtly revived his contention that Obama is downplaying the Iran threat.
"We have seen Iran marching, marching with single-minded determination toward the same goal, authenticated again today by the IAEA," the U.N. nuclear regulatory body, McCain said at the outset. President Mahmoud Ahmadinejad, he continued, "has threatened to wipe Israel off the face of the earth, and represents a threat to every country in the region -- one we cannot ignore or minimize."
For her part, Clinton counts the pro-Israel community as a redoubt of support in her increasingly unlikely bid to claim the Democratic nomination and has made clear she will not cede it. In the last debate with Obama, Clinton said she would "obliterate" the Iranian regime should it launch a nuclear strike against Israel.
The trio of candidates isn't the only draw to what promises to be a crowded three days: Defending the Bush administration in its waning days will be Condoleezza Rice, the secretary of state. The leaders of both parties in both houses of Congress also plan to speak.
It marks a pleasant change for AIPAC, which has been dogged in recent years by critics who have accused the lobby of helping the Bush administration win support for the Iraq war, even though lawmakers have denied repeatedly that AIPAC played any role in rallying congressional backing for the war.
It is also the first policy conference since last summer, when AIPAC agreed in principle to continue to fund the defense of two former staffers facing trial for dealing in classified information, removing at least partially the opprobrium that the group had abandoned two loyal soldiers.
More substantially, AIPAC is scoring major lobbying successes in Congress. A bill under consideration that would create certification to show that Israel is maintaining a qualitative military edge in the region already has garnered major support.
And while the Democrat-controlled Congress and Bush are deadlocked over just about every major budget issue, lobbyists at AIPAC are confident that Congress will adopt the president's plan this year to start increasing assistance to Israel from an average of $2.4 billion annually to $3 billion.
The policy forum's highlight is its dinner June 3 at the cavernous Washington convention center, which organizers say is the largest seated meal in the nation's capital. AIPAC leaders call out the roster of lawmakers in attendance and usually garner a bipartisan majority of both houses, underscoring the group's main point: support for Israel crosses the aisle.
Partisanship can raise its head, and did so a year ago when Vice President Dick Cheney and Israeli Prime Minister Ehud Olmert both called for Jewish support for the Iraq war -- and when Pelosi earned scattered boos for decrying the war.
An AIPAC spokesman said such manifestations are marginal."As thousands of members arrive for the conference, our role is to nurture the bipartisan nature of support for Israel and to strengthen the ties with all sectors of society," the spokesman said.
More than 7,000 activists are expected to attend, including 1,200 students.
Olmert is attending in person and likely will press for support for his recent stepped-up efforts to negotiate peace with the Palestinians and Syria. Insiders say AIPAC already is preparing the ground to shepherd support for such initiatives through Congress.
June 4 is the designated lobbying day for the activists. They are expected to push for Iran sanctions and back two non-binding resolutions. One recognizes Israel's efforts to arrive at a two-state peace with the Palestinians and calls for greater support for the effort from Arab countries, and the other seeks increased sanctions on Iran, including a ban on the sale of refined petroleum.