Just about everyone, according to Steve Clemons who was there over the weekend:
But unlike the clamor of candidates to speak at the annual AIPAC conference or to appear at various national security forums in Israel, this important Michigan-based conference of the great and the good among Arab Americans was given a frosty shoulder by leading candidates of both parties, and I think that is outrageous. [...]
First of all, I want to applaud the fact that Ron Paul, Mike Gravel, Dennis Kucinich, and Bill Richardson took the time to be at this important assembly of Arab Americans.
Let me clap with just one hand the fact that Hillary Clinton, John Edwards, and Barack Obama sent videotaped greetings and had "surrogates" represent them in exchanges with the large audience. [...]
None of the Republicans other than Paul had a serious presence there. Mitt Romney had someone put out some brochures -- but neither he, nor Rudy Giuliani, nor Fred Thomspon, nor John McCain sent anyone to meet with national leaders of the premier Arab American leadership conference in the nation.
It's a bit of a sad state of affairs. Obviously, politicians shouldn't feel any particular compulsion to agree with the Arab-American Institute's policy views if they think they're wrong on the merits, but it hardly seems like too much to ask for a little engagement with this bloc of people.