New Jersey Democratic Sen. Bob Menendez appears to be heading into some serious trouble in the November midterm elections, and few are taking notice.

Listening to Senate Majority Leader Mitch McConnell, the focus for Senate Republicans is picking up seats in states like Arizona, Nevada, Tennessee, Montana, North Dakota, Missouri, Indiana, West Virginia and Florida.

Leadership’s goal is to retain the seats in competitive GOP races — like the vacancy left behind from Sen. Jeff Flake in Arizona — and pick up seats in tight elections, like Sen. Heidi Heitkamp’s of North Dakota.

Yet, another state — New Jersey — is looking more and more competitive with every passing week.

While former Secretary of State Hillary Clinton took the state with 14 percent more of the vote than President Donald Trump in 2016, voters are becoming increasingly iffy about Menendez, a man who has been at the center of one of the biggest political scandals since the 2016 election. (RELATED: Reid Asked Obama To Help Menendez Donor)

The scandal revolves around a Florida eye doctor and longtime friend of Menendez, Dr. Salomon Melgen, who lavished the senator with large campaign donations and held private fundraisers for him at his 6,500-square-foot home in North Palm Beach, Fla. Melgen did all of this in exchange for Menendez’s assistance in navigating government disputes.

The doctor was convicted of 67 counts of Medicare fraud and sentenced to well over a decade in prison in late April 2017. (RELATED: Florida Doctor Found Guilty Of 67 Counts Of Fraud)

The Senate Ethics Committee conducted a months-long investigation into the matter and found Menendez in violation of federal election and ethics laws in late April.

“The Committee has found that over a six-year period, you knowingly and repeatedly accepted gifts of significant value from Dr. Melgen without obtaining required Committee approval, and that you failed to publicly disclose certain gifts as required by Senate Rule and federal law,” the committee wrote in an April 26 letter to Menendez.

“Additionally, while accepting these gifts, you used your position as a Member of the Senate to advance Dr. Melgen’s personal and business interests. The Committee has determined that this conduct violated Senate Rules, federal law, and applicable standards of conduct,” the committee wrote.

The New Jersey senator is charged with repaying the “fair market value” of all “impermissible gifts not already repaid.”

Menendez narrowly escaped a federal retrial, after a federal judge acquitted him of many of the charges in January.

The scandal appears to have rattled Menendez’s favorability with New Jersey voters.

Menendez, a two-term senator and former congressman, is only leading Republican challenger Bob Hugin four percentage points, according to a May 26 Fairleigh Dickinson University poll. That is markedly down from April, when Monmouth University pegged Menendez with a strong 21 percentage point lead. Quinnipiac had Menendez up 17 points in March.

All three polls have, within reason, similar sample sizes and margins of error. The Fairleigh Dickinson poll has a margin of error or plus or minus 3.5 percentage points and a sample size of 856. Monmouth University’s poll has a margin of error of plus or minus 3.9 percentage points for voters and a sample size of 632. Quinnipiac has the largest sample size — 1,052 — and a margin of error 4.2 percentage points.

Another factor that could hurt Menendez is he polls lower than most election officials in the state and even President Donald Trump. Only 22 percent of New Jerseyans have a positive impression of Menenedez, a May Rutgers University poll found.

RealClearPolitics has the state leaning only “likely Democrat,” but Republicans, notably, rarely eclipse the 50 percent mark in statewide races. It isn’t clear whether or not Hugin will be able to garner that many votes, but the Fairleigh Dickinson poll has 42 percent of voters remaining undecided — an amount large enough to sway the final election in November.

Hugin, a former Marine, was late to jump in the race, announcing his bid to take on Menendez in mid February.

“When we had all of these polls come out in the beginning, we were down by 17, down by 21. The main takeaway from those early polls was that Menendez was incredibly underwater for a two-term incumbent senator,” Hugin spokesman, Nick Iacovella, told The Daily Caller News Foundation. “It is clear now that voters are looking towards someone who is not a 25-year corrupt politician.”

Hugin’s team attributes some of their gains to New Jersey votes, many of them Democrats, finding out about Menendez’s relationship with Melgen. The story got widespread national coverage; but for one reason or another, many voters did not understand the full extent of the details.

The Republican candidate’s team launched a two ad buys against Menendez in early May in an effort to tell voters all about the senator’s past year.

WATCH:

Democrats attack Hugin for his previous role as an executive with pharmaceutical company Celgene. Hugin retired from the company as executive chairman in early February to pursue his campaign against Menendez.

The argument against Hugin is while he was serving as executive chairman, the company settled a whistleblower lawsuit that alleged Celgene repurposed a leprosy drug for unapproved cancer treatments. Celgene paid $280 million to settle the lawsuit.

That agreement settled a suit in a federal court in California that alleged Celgene submitted false claims to Medicare, arguing abuse, which is what Menendez was wrapped up in with Melgen.

Hugin is promising to fully fund his own campaign, much like the president and other Republican candidates have pledged since 2016. He is largely expected to beat out all other Republican candidates in the field. GOP voters head to the ballot box June 5 to decide the candidate they want to challenge Menendez.

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