AIPAC, J Street, what is the difference anway

"Even the competition with the new Israel lobby group on the left, J Street, did not succeed in shaking the standing of AIPAC, at least in terms of the numbers of participants, with 7,500 people signing up, a record high for the group." The lousy J Street? Who would want them to succeed anyway? They are a branch of AIPAC, no more. Today, they took up an ad in the New York Times. They called on Palestinians to desist from inciting violence but did not call on Israelis to desist from inflict violence.