NEW YORK - Prosecutors expect to call their final witness on Friday in U.S. Senator Bob Menendez's corruption trial, paving the way for the once-powerful lawmaker to mount his defense. 

During six weeks in Manhattan federal court, prosecutors have sought to portray the senior New Jersey senator as a greedy politician who attempted to help foreign governments and interfere in criminal probes into associates who bribed him and his wife with gold bars, cash, a car, and home payments.

Menendez has pleaded not guilty to 16 criminal charges including bribery, fraud, acting as a foreign agent and obstruction. His wife, Nadine Menendez, has also pleaded not guilty and is set to go on trial in August.

Bob Menendez's defense lawyers have sought to distance him from his wife's financial dealings. They have portrayed actions that prosecutors have described as nefarious - such as the senator aiding the governments of Egypt and Qatar, or conversations with prosecutors about his associates' cases - as routine legislative work and constituent advocacy.

"It's not enough to prove that Senator Menendez or Nadine Menendez received a benefit and that Senator Menendez took an official act," said Paul Tuchmann, a partner at law firm Wiggin and Dana and former federal prosecutor who is not involved in the case. "They have to prove it is one for the other." 

Menendez, 70, stepped down as chair of the Senate Committee on Foreign Relations after being charged in September, but has resisted calls from fellow Democrats to resign from the Senate. He is running for re-election in the Nov. 5 election as an independent. 

His lawyers have said they may call 21 witnesses, though they have not named them.

In a court filing on Thursday, prosecutors said defense lawyers told them they would call Menendez's older sister to testify about the senator's "personal and family history of storing cash outside of banks." 

Menendez's defense lawyers did not immediately respond to a request for comment. A spokesperson for the U.S. Attorney's office in Manhattan declined to comment. 

The defense will have to contend with damaging testimony from government witnesses. Jose Uribe, an insurance broker who pleaded guilty to bribing Menendez, testified that after he helped Nadine Menendez buy a $60,000 Mercedes-Benz, the senator told him he "saved" two of his associates from New Jersey state probes.

Philip Sellinger, New Jersey's top federal prosecutor, testified that after he expressed interest in that job in late 2020, Menendez told him that he thought businessman Fred Daibes - who had been indicted for fraud - was being treated unfairly. Daibes is on trial alongside Menendez, having pleaded not guilty to bribing the senator. 

In testimony that could help the defense, Sellinger said he never felt Menendez pressured him to do anything improper, and Uribe said he never discussed Nadine Menendez's car payments with Bob Menendez.

But prosecutors will ask jurors to use common sense to make inferences about Menendez's knowledge, said Allon Lifshitz, a former federal prosecutor who is not involved in the case. Those inferences include that Menendez knew discussing individual cases with prosecutors was inappropriate, and that because he and his wife shared details of their lives, they must have discussed the bribes, said Lifshitz, now a partner at law firm Cohen & Gresser. 

"The prosecution will stand up and tell the jury that when Mrs. Menendez asks the senator to do favors for people in her life, he had to know that at the same time she was receiving the Mercedes, the gold bars and the mortgage payments," Lifshitz said.

(Reporting by Luc Cohen in New York; Editing by Noeleen Walder and Daniel Wallis)

By Luc Cohen