Jury selection began today in the corruption trial of Democratic Sen. Robert Menendez, a case that could undermine his re-election chances and determine which party controls the Senate after November’s elections.

Menendez, 70, and two New Jersey businessmen are accused of bribery. The senator’s wife Nadine is also accused, but she will be tried separately. All four have pleaded not guilty.

Once cleared, Menendez hopes to run again for a fourth term in the Senate as an independent. Recent polls, however, show he is unpopular with New Jersey voters, and several Democratic senators, including Cory Booker, have called for him to resign. Democrats and the independents who support them have a narrow majority (51-49) in the Senate.

According to prosecutors, the Menendezs received cash – much of which was found hidden in clothing in their home – as well as gold bars and a Mercedes-Benz, in exchange for the senator’s influence in New Jersey and for helping the governments of Egypt and Qatar. The senator allegedly promised to help Egypt secure an arms contract and other military aid while helping his co-defendant, Wael Hanna, an American-Egyptian businessman, secure a lucrative monopoly on the certification of halal meat exports to Egypt. He also allegedly tried to help co-defendant Fred Dibes receive millions of dollars from a Qatari investment fund and intervened to stop a federal investigation into him in New Jersey.

The offenses were committed between 2018 and 2023.

A fifth defendant, Jose Uribe, pleaded guilty to bribery and fraud in March and agreed to cooperate with prosecutors.

Nadine Menendez’s trial has been set for July 8. The case was separated after her lawyers explained that she is suffering from a serious illness that requires a long recovery.

Robert Menendez’s attorneys hinted in court documents that if he testifies, he could blame his wife, revealing marital conversations that would exonerate him, incriminating her. Menendez may explain what was discussed at dinners with Egyptian officials and present his wife’s justifications for why Hanna and Uribe gave her monetary gifts.

Defense attorneys may also call a psychiatrist who will testify that the senator routinely hid cash in his home because he was “afraid of missing it.” It was a habit he acquired after the Cuban government confiscated his family’s property – before he himself was born – and his father killed himself after his son stopped paying his gambling debts.

This is Menendez’s second trial on corruption charges. In 2017, a mistrial was declared after jurors could not reach a verdict on whether the senator broke the law by providing assistance to a wealthy eye doctor, Salomon Melgen, in exchange for lavish gifts and contributions to his political career.

Menendez was chairman of the powerful Senate Foreign Affairs Committee until last September, when he resigned after being impeached.