Days before the inaugural conference of the left-wing pro-Israel group J Street, critics’ attacks on the organization are having an effect on the planned event.

At least 10 members of Congress in recent days have removed their names from the conference’s 160-person congressional host committee, many after inquiries from a writer at a prominent conservative magazine. J Street canceled a poetry session scheduled for the conference after controversial remarks made by one of the planned participants were publicized in that same magazine. And the Israeli Embassy announced it would be sending only an observer, not Ambassador Michael Oren, to attend the conference.

Meanwhile, J Street announced it had secured a high-ranking Obama administration official to keynote the Oct. 25-28 event in Washington: President Obama’s national security adviser, James Jones.

The criticism underscores the controversy J Street has stirred in the Jewish community, particularly given the warm reception it has gotten from Obama administration officials. Many pro-Israel critics say J Street’s advocacy – including for U.S. intervention to support a two-state solution and against further Iran sanctions right now -- undermines the Israeli government and Israel’s welfare. J Street, which calls itself “pro-Israel, pro-peace,” says the policies it pursues are in Israel’s best interests.

The pro-Israel group Stand With Us was planning this week to place advertisements expressing concern with J Street in the Washington Post and Washington Jewish Week.

The trouble for J Street’s poetry session came last week, when the Web site of The Weekly Standard posted a video in which poet Josh Healey, a scheduled participant, talks about how for his friends "Anne Frank is Matthew Shepard" and "Guantanamo is Auschwitz.” In another poem the Standard reprinted, Healey wonders whether "the chosen people" have been "chosen to recreate our own history, merely reversing the roles with the script now reading that we're the ones writing numbers on the wrists of babies born in the ghetto called Gaza?"

J Street canceled the poetry session on Monday. The group’s executive director, Jeremy Ben-Ami, said that “as J Street is critical of the use and abuse of Holocaust imagery and metaphors by politicians and pundits on the right, it would be inappropriate for us to feature poets at our conference whose poetry has used such imagery in the past and might also be offensive to some conference participants.”

Another a session, which is not officially part of the conference but to which J Street is giving hotel space during the event, will include writers who have harshly criticized Israel and questioned its right to exist as a Jewish state. It is sponsored by blogger Richard Silverstein; J Street officials said they have nothing to do with the program.

Members of Congress began taking themselves off the conference host committee last week. Most of the 10 who removed themselves blamed staffers who they said were not knowledgeable about the positions J Street espouses before agreeing to put their boss on the committee. (J Street acknowledged that the presence of Sen. Kirsten Gillibrand (D-N.Y.) on the list was an error; Sen. Chuck Schumer (D-N.Y.) originally agreed but pulled out before J Street released the committee list last month.)

In an e-mail to supporters, J Street blamed The Weekly Standard for the withdrawals, saying the magazine’s “thuggish smear tactics” were having an impact on Capitol Hill. The e-mail urged supporters to fight back by calling members of Congress to thank them for being a part of the conference host committee.

Michael Goldfarb, the editor for The Weekly Standard who wrote about J Street, said he takes J Street’s attack against him as a compliment.

“They say the 'thuggish smears are having an impact,'” he said. “They're not having an impact because they're smears, they're having an impact because they're true.”

On Tuesday, the Israeli Embassy in Washington released a statement saying it would send an observer to the conference and would "follow its proceedings with interest," but Ambassador Michael Oren, whom J Street had invited, would not attend. The statement added that the embassy has been "privately communicating its concerns over certain policies of the organization that may impair the interests of Israel."

J Street’s director of policy and strategy, Hadar Susskind, said he sees the attacks on the organization and its conference as “a sign that we are waking people up,” and making a mark on the U.S.-Israel relationship.

He also noted that more than 1,200 people had signed up to attend the conference.