AIPAC wary of a congressional no vote

America's pro-Israel lobby is finding it difficult to overcome widespread opposition in Congress to the use of force against Syria, according to AP.

The groups are considered to be some of the most influential lobbyists on Capitol Hill, but officials with several of the pro-Israel groups say they are running into rare resistance from lawmakers, even among staunch Israel advocates.

Pressure rises as Congress returns Monday from a holiday recess.

Among those that have released public statements and made private calls to lawmakers to urge them to vote "yes" are The American-Israeli Public Affairs Committee, or AIPAC, the Anti-Defamation League and the Simon Wiesenthal Center.

Officials with several pro-Israel groups say they are encountering an opposition compounded by pure political motivations, especially among Republicans.

They said they will continue to lobby -- AIPAC is bringing some 250 pro-Israel activists to Washington in the coming days to push for the authorization -- but they have also told the White House that only a powerful and direct personal appeal from Obama himself is likely to have an impact.