WASHINGTON — Democratic U.S. Reps. Lois Frankel, Patrick Murphy and Joe Garcia of Florida are in Israel for the week along with more than 30 other Democratic House members — trips paid for by an arm of a powerful lobbying group.

Next week, freshman Republicans head off on the same trip, paid for by the American Israel Education Foundation, which Frankel described in a news release as an "independent, nonprofit charitable organization."

It is, in fact, an offshoot of the lobbying group American Israel Public Affairs Committee, which gets around restrictions on privately paid travel by using the educational arm, an arrangement government watchdogs have criticized. One of the big AIEF boosters: billionaire casino mogul Sheldon Adelson, who poured millions into campaigns to defeat President Barack Obama last year.

In 2012, Rep. Kevin Yoder, R-Kan., caused a scandal after it was revealed the FBI had investigated him skinny dipping in the Sea of Galilee during a trip the year before. Rep. Steve Southerland, R-Panama City, jumped into the water with his daughter, but they were clothed.

Murphy and Frankel disclosed that they were going, with Garcia doing so Wednesday morning. But AIPAC refused to provide the full list of lawmakers who made the trip, presumably along with family members. An AIPAC spokesman referred questions to the office of Democratic Whip Steny Hoyer. A spokeswoman for the Maryland lawmaker also would not provide names and referred a reporter back to AIPAC.

Six years ago, the House banned groups from paying for extended trips as part of the fallout from the scandal over lobbyist Jack Abramoff. But a loophole allowed educational foundations to pick up the tab. The Israel trips are estimated at $10,000 per person.

"Members of Congress feel indebted to someone who provides them with a week's long vacation. It's lobbying and it's more effective than direct lobbying on Capitol Hill," said Craig Holman of the watchdog group Public Citizen, who helped draft the 2007 laws. He said the loophole has been steadily abused and privately-paid travel is back to pre-reform levels.

"This is not what lobbying should be about," Holman said. "It should be about providing information and expertise so lawmakers can make better decisions, not trying to buy their favors with gifts and travel junkets."

Frankel said the delegation will meet with key leaders — both Israelis and Palestinians — to gain insight on issues of security, diplomacy, defense cooperation and more.