Last week was not a good one for our senior senator.

On Tuesday, a judge in Newark ruled that the trial of U.S. Sen. Bob Menendez on corruption charges next month will go ahead as scheduled despite the senator's appeal on technical grounds.

And then on Thursday a judge in Florida agreed to delay until after that trial the sentencing of the senator's co-defendant in the corruption trial, Palm Beach eye doctor Salomon Melgen, on counts of Medicare fraud.

That set off speculation that the 63-year-old Melgen would make a deal with the prosecution to turn state's evidence against Menendez in return for a lighter sentence.

There was no immediate indication that such a deal is in the offing. But one close observer of the case said that such a deal looks like the obvious option for Melgen.

"Melgen played all of his cards and he's got one card left, one and that's to cooperate with the prosecution in the Menendez trial," said Tom Anderson. "They're pushing for 30 years to life. Faced with that and one last card to play, does he really have a choice?"

Anderson is a Fort Lauderdale resident who is an investigator for the National Legal and Policy Center, a government watchdog group. In 2013, he unearthed the transcript of a Senate Foreign Relations Committee hearing in which Menendez advocated on behalf of a company owned by Melgen in its efforts to enforce a lucrative port-security contract with the Dominican Republic.

After the New York Times reported on that transcript, it found its way into the indictment of Menendez and Melgen.

In that hearing, the senator told officials from the State and Commerce departments that Dominican officials "don't want to live by that contract" and went on to say "You have, you know, some of the other countries that I have mentioned today with arbitration awards that have gone against them, and yet, they don't want to live by that. Well, what are we willing to do?"

Does that constitute "a formal exercise of government power?"

That could be key to the case.

The prosecution in the trial, which is set to begin Sept. 6 in Newark, is seeking to prove that the senator did favors for the ophthalmologist in return for such goodies as trips on Melgen's private plane to his house in the Dominican Republic for lavish parties.

The defense counters that any actions the Democratic senator may have done for his friend did not rise to the level of illegality.

They're relying on a decision last year in which the U.S. Supreme Court reversed the conviction of former Virginia Gov. Bob McDonnell in a similar case. McDonnell was also accused of accepting various goodies from a supporter. But the high court ruled that he could not be convicted of corruption unless he had engaged in "the formal exercise of government power" in return for the gifts.

Menendez had hoped to have the case against him thrown out on similar grounds. But U.S. District Court Judge William Walls has ruled that the case will go to trial as scheduled. The likely result is that the prosecution will get to present its entire case. Then the judge could decide whether the case got to the jury.

It will be up to the judge to decide whether that and the other favors the senator allegedly did for his friend, such as intervening with Medicare officials in his billing disputes, meet the standard set in the McDonnell case. But the prosecution case will be a lot stronger if Melgen turns against Menendez.

There's a lot riding on his decision, including the possible control of the Senate.

If Menendez has to leave the Senate while Chris Christie is still governor, then Christie gets to name a Republican successor who will serve until the election of November 2018.

That one vote in the Senate could be crucial when you consider what happened in that recent vote on repealing Obamacare. It lost by one vote when Arizona Sen. John McCain decided to defy The Donald.

But if the GOP majority could be increased from the current 52 to 53, then Trump would be in a much better position to get his favored legislation past the Senate.

There's a lot riding on this game.

And after last week, it looks like the deck is stacked against the senator.

ADD: MENENDEZ WAS ONCE THE SINGER: In Hudson County circles, Menendez is still known as the guy who turned on his political mentor and sang like a mockingbird.

The mentor was the late Billy Musto, who was once the mayor of Union City.

Menendez later also served as mayor of Union City - and he served himself quite well when it came to the zoning on a rowhouse he sold at a big profit.

Here's a passage from the New York Times 2006 obituary of Musto that nicely summarizes the way Menendez turned on his mentor:

"One of Mr. Musto's proteges was Robert Menendez, who started out as a mayor's aide and rose to become a powerful Democratic congressman in New Jersey, recently appointed to the United States Senate.

"The two were very close, like father and son, many said, until Mr. Musto was investigated for corruption and Mr. Menendez became a government witness and testified against him. That testimony helped convict Mr. Musto, along with six other men, of racketeering. His conviction withstood appeals, and Mr. Musto eventually had to leave office. He spent three years in federal prison."

Will history repeat itself?

We will soon see.