Menendez’s spokeswoman said the senator had no idea Permuy was involved with ICSSI, which wants to X-ray port cargo as part of a contract worth as much as $500 million or more.

But ethics watchdogs have their doubts.

“That’s the howler of the day. I don’t see how the senator couldn’t have known about it,’’said Ken Boehm, chairman of an ethics watchdog group called the National Legal and Policy Center.

“Permuy is not just a former staffer,” Boehm said. “He did two stints with Menendez. Menendez advocated for this issue. And they’re together on this council? How could Menendez not really know?”

Boehm points out that Melgen’s cousin, Vinicio Castillo Seman, told reporters publicly, privately and in writing that Permuy was involved with the ICSSI deal. Castillo mentioned Permuy, a former assistant U.S. defense secretary, to rebut critics of ICSSI who noted that eye doctor Melgen had no security background.

“Why would Castillo go out of his way to say we’re going to hire this guy to run the thing?” Boehm asked.

Permuy appears to be on a first-name basis with former Secretary of State Hillary Clinton, who has received campaign money from Melgen as well. Permuy worked for Menendez in the mid-‘90s and then again in the early 2000s.

In June 2012, during the United States-Spain Council’s forum in Menendez’s home state of New Jersey, Clinton thanked “Pedro” for serving as president of the council and for his involvement in the forum, attended by Spain’s king. Menendez is the honorary chair of the group.

Clinton also name-dropped Francisco J. Sánchez, the Commerce Department’s undersecretary for international trade.

A month later, Sanchez was giving testimony at the Senate Foreign Relations Subcommittee on the Western Hemisphere when Menendez brought up contracting issues in the Dominican Republic.

“You have another company that has American investors that ... has a contract actually given to it by the — ratified by the Dominican Congress — to do X-ray of all of the cargo that goes through the ports,” Menendez said. “And they don’t want to live by that contract either.”

Menendez didn’t mention ICSSI by name.

Around the time of the council’s forum, Melgen’s Vitreo-Retinal Consultants company contributed $400,000 to a Democratic political committee, Majority PAC, that supported Menendez. In October, Vitreo-Retinal contributed another $300,000.

Majority PAC then contributed $582,500 to boost Menendez’s re-election.

The year before, Melgen and his wife contributed $40,000 to a group called the Fund to Uphold the Constitution, which successfully fended off a Republican recall effort. Prior to that, the Melgens contributed $60,400 to the Democratic Senatorial Campaign Committee when Menendez chaired it in 2009 and 2010.