TRENTON, N.J. (AP) — U.S. Sen. Bob Menendez, who pleaded not guilty this week to bribery charges, occupies the same seat as the last senator to be convicted of such a charge: Harrison "Pete" Williams.

The charges against the senators, both Democrats, play into a persistent — and not totally baseless — stereotype of New Jersey politicians on the take.

U.S. Sen. Robert Menendez (D-New Jersey). (AP Photo/Pablo Martinez Monsivais, File)

The state's a place where Gov. Chris Christie made his name by winning more than 130 corruption convictions during the seven years he spent as U.S. attorney, and where real political figures became the basis for some famous fictional corrupt characters — Nucky Thompson from "Boardwalk Empire" and Carmine Polito in "American Hustle."

Just this century, mayors of Newark, Trenton and Camden have been sent to prison, and scandals prompted a governor to resign and a U.S. senator to drop out of a re-election bid.

Julian E. Zelizer, a professor of history and public affairs at Princeton University, said the Menendez and Williams cases, which are among the 12 times a sitting senator has been indicted, are very different.

"This involves the normal relationships between legislators and lobbyists and special interests," Zelizer said of the case against Menendez. "Harrison Williams got caught up in a special kind of case ... they were seeing how far legislators might go if tempted."

Williams, an enormously popular politician who spent 23 years in the U.S. Senate, is the highest-ranking New Jersey politician to be convicted of corruption charges.

He was also the biggest catch in the late 1970s FBI operation known as "Abscam," the one retold in "American Hustle" that also netted six members of Congress and 13 other people. He was convicted in 1981 of bribery, conflict of interest and conspiracy charges for accepting bribes from a fake Arab sheik who wanted government help to clear the way for investments of millions of dollars in American business ventures.

Williams spent nearly two years in federal prison and died in 2001. He maintained his innocence, saying he was set up by the government.

In Menendez's case, the legal question is less about what he did than whether his actions broke the law by intervening in government activities on behalf of Salomon Melgen, a Florida eye doctor and major campaign contributor who was also charged in the case.

The government says Melgen paid for luxury travel for Menendez in exchange for favors, including intervening in a Medicare dispute worth millions of dollars. Melgen pleaded not guilty alongside Menendez on Thursday.

Menendez maintains he did nothing illegal by helping a man who is not just a supporter but also a longtime friend.

Williams looms in the background of the case in an odd way.

His connections with Melgen first received scrutiny just before Menendez's 2012 re-election when The Daily Caller, a conservative website, reported that authorities were investigating whether Menendez had traveled on Melgen's private plane to the Dominican Republic to have sex with prostitutes. The site posted video of two women making the claim.

In 2013, a Dominican prosecutor said a lawyer there discredited the story by saying he was paid to find prostitutes who would claim to have had sex with Menendez.

It's not clear who sent emails to the FBI, a political watchdog group and others that initially made the prostitution accusation, but they were signed "Peter Williams."

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