Sorry I said "currently-serving" in the title but on closer inspection this list is a little old as it has some people that are no longer in congress. Also there may be a few people who don't belong on the list, like Bernie Sanders, who actually does stand against Israel on a lot of stuff and denies having a second citizenship.

However on the other side of the coin, here's evidence for Jane Harman:

In 2009 it was revealed that the NSA had secretly taped conversations of Congresswomen Jane Harman [pictured above on the right with Israeli Knesset Speaker, Dalia Itzik] negotiating with two AIPAC spies accused of giving sensitive information about US military activities to the Israeli government. In the taped conversation she is being asked to dismiss their espionage charges in return for large political contributions and a chairmanship of the US Intelligence Committee! One has to assume that they thought they could actually "arrange" for this to happen. This information was secretly revealed by the NSA to Nancy Polosi prior to the selection of the committee chairman and was likely a factor in Harmon's failure to obtain this highly sensitive position. After all was said and done, however, the case against the two Israeli lobbyists was dismissed -- against the insistance of the FBI. No satisfactory reason has been given for this.

Unfortunately, such an act of treason remains unchallenged and Jane Harman remains at her congressional job and enjoys being the third wealthiest member of Congress.