Updated 2:30 p.m.

NEWARK, N.J. (AP) — U.S. Sen. Bob Menendez pleaded not guilty Thursday to charges that he accepted nearly $1 million in gifts and campaign contributions from a longtime friend in exchange for a stream of political favors.

Menendez entered the plea before a federal judge in Newark, one day after he promised to be vindicated and declared that he’s “not going anywhere.”

The indictment alleges he used the power of his Senate seat to benefit Salomon Melgen, a wealthy Florida eye doctor who prosecutors say provided the senator with luxury vacations, airline travel, golf trips and tens of thousands of dollars in contributions to a legal defense fund.

Melgen also entered a not guilty plea, and Judge William Walls set a tentative July 13 trial date.

Prosecutor Peter Koski said the “government is ready for trial at the earliest possible date.”

The investigation that led to the indictment came into public view when federal authorities raided Melgen’s medical offices in 2013. It will almost certainly lead to a drawn-out legal fight between Menendez and a team of Justice Department prosecutors who have spent years investigating his ties to Melgen.

It will require prosecutors to prove that a close and longtime friendship between the men was used for criminal purposes, and it is likely to revive the legal debate about the constitutional protections afforded to members of Congress for acts they take in office, which Menendez has already signaled as a possible line of defense.

Related story: New Jersey Sen. Bob Menendez Indicted on Corruption Charges

The criminal charges brought Wednesday cloud the political future of the top Democrat — and former chairman — of the Senate Foreign Relations Committee, who has played a leading role on Capitol Hill on matters involving Iran’s nuclear program and U.S. efforts to improve ties with Cuba.

Menendez said he would temporarily step aside from his role as top Democrat on the committee but appeared more defiant than ever at a hastily called news  conference that felt more like a political rally, with enthusiastic supporters cheering him on.

“I’m outraged that prosecutors at the Justice Department were tricked into starting this investigating three years ago with false allegations by those who have a political motive to silence me. But I will not be silenced. I am confident, at the end of the day, I will be vindicated, and they will be exposed,” Menendez told reporters, adding: “This is not how my career is going to end.”

He later said: “I am not going anywhere. I’m angry and ready to fight because today contradicts my public service and my entire life.”

Melgen’s attorney did not return a call seeking comment Wednesday.

The news was met with what appeared to be a coordinated round of supportive statements from national and New Jersey Democrats who rallied around the senator.

“Bob Menendez is one of the best legislators in the Senate and is always fighting hard for the people of his state. I am confident he will continue to do so in the weeks and months ahead,” said U.S. Sen. Chuck Schumer of New York.

But the indictment also raised questions about other money Melgen has contributed. An aide to U.S. Sen. Amy Klobuchar of Minnesota said Wednesday night that she would return campaign contributions she received from Melgen as well as from Menendez. Klobuchar matches the description of a lawmaker called “Senator 1” in the indictment, though she was not accused of wrongdoing.

The indictment from a grand jury in Newark contains 14 counts — including bribery, conspiracy and false statements — against Menendez and charges Melgen, a political donor to Menendez and other Democrats. Menendez had already acknowledged that he had taken several round-trip flights to the Dominican Republic on Melgen’s luxury jet that, initially, were not properly reimbursed. But the document spells out many additional gifts, such as a Paris hotel stay and access to a Dominican resort, that prosecutors say were never reported on financial disclosure forms.

In exchange for those and other gifts, prosecutors allege, Menendez sought to smooth approval of the visa application process for several of Melgen’s foreign girlfriends, worked to protect a lucrative contract Melgen held to provide cargo screening services to the Dominican Republic and intervened in a Medicare billing dispute on the doctor’s behalf worth millions of dollars.

In 2013, in an email exchange one day after Melgen and Menendez had golfed together in Florida, Menendez told a staffer to contact U.S. Customs and Border Protection to stop them from donating shipping container monitoring and surveillance equipment to the Dominican Republic, according to the indictment. Melgen had a contract to provide exclusive cargo screening services in Dominican ports, and the Customs and Border Protection plan would have hurt his financial interests, prosecutors say.

In advocating for Melgen’s business interests, prosecutors say, Menendez pursued meetings with the heads of executive agencies and tried to solicit the help of other U.S. senators.

Menendez has acknowledged taking actions that could benefit Melgen, among them contacting U.S. health agencies to ask about billing practices and policies. But the lawmaker has said he did nothing wrong and the interactions he had with the doctor were reflections of a close friendship dating two decades.

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