He then identified a handful of close Jewish friends and advisers.
IRAN, RACE
Questioners also drilled him on his willingness to meet with US foes like Iranian President Mahmoud Ahmadinejad, who has denounced Israel and denied the Holocaust occurred.
Obama, while critical of the Iranian president, said direct diplomacy with Iran would be more effective than no engagement. "I believe the policy of not talking to our enemies has not worked," he said.
Not everyone agreed.
"I think that our commander in chief should not propose talks with someone who calls for the destruction of Israel," Stephen Lippy, 51, told Reuters.
Some said they were concerned about Obama's support for the Jewish state before his visit but came away satisfied.
"I think today convinced me," said Aaron Levitt, 32, a rabbi and Democrat. "I feel like he made it very clear that Israel's at the centre of his Middle East policy and would be a very important ally in his presidency."
Obama, who would be the nation's first black president, addressed the issue of race directly, saying he was concerned that a historic connection between African Americans and Jewish Americans had slipped.
"I want to make sure that I am one of the vehicles by which we can rebuild those bonds," he said.
A sample of audience members said race would not affect their votes, while admitting it could be an issue for some.
"I think that people don't realise it, but I do think it's there," said Obama supporter Barbara Schneider, 55.
"As a Jew, would I vote for a black person? Sure," said Lippy. "But...my issue is will he be the best commander in chief when it comes to assisting Israel and our other Western democratic allies."
