With less than five weeks until Election Day, Sen. Bob Menendez, the incumbent Democrat, appears to hold an advantage over Republican challenger Bob Hugin, although a pair of polls released Wednesday show differing amounts of separation between the two.

A Fairleigh Dickinson University poll released in the morning said Menendez leads Hugin among likely voters 43 percent to 37 percent. That lead decreases to five points, 37 percent to 32 percent, among registered voters, and when the four-point margin of error is taken into consideration, "the election remains anyone's game," poll director Krista Jenkins said in a statement.

A Quinnipiac University poll released later in the day gave Menendez an 11-point lead — 53 percent to 42 percent — among likely voters, propped up by women and non-white voters.

Women back Menendez by 57 percent to 38 percent over Hugin, and the incumbent leads 67 percent to 26 percent among non-white voters, in the Quinnipiac poll. Support for the candidates is evenly split between men and white voters.

What is clear is that the race between the two men is competitive and certainly closer than would typically be expected in a blue state like New Jersey, where several Republican-held congressional seats are expected to either flip or be strongly contested this year by Democratic challengers on the strength of President Donald Trump's unpopularity.

Republicans have a narrow majority in the Senate, with 51 seats to Democrats' 49. Menendez's re-election is considered crucial to any chance, however small, of Democrats' reclaiming control of the Senate.

New Jersey voters haven't sent a Republican senator to Washington in four decades.

But Menendez, who is seeking a third full term, is being dragged down by favorability ratings in the 30s — compared with about half of voters who view him unfavorably — after his corruption trial last year that ended in a hung jury.

In addition, a majority of likely voters — 59 percent, according to Quinnipiac — think Menendez is not honest, compared with a quarter who think he is.

Federal prosecutors later dropped the charges against Menendez, but he was then "severely admonished" by the Senate Ethics Committee and ordered to repay gifts he had accepted.

Hugin, a former CEO of the pharmaceutical company Celgene who has poured many millions of his own fortune into the race, has tried to capitalize with campaign ads targeting Menendez's ethics and offering himself as a moderate alternative who supports abortion rights, same-sex marriage and a pathway to citizenship for undocumented immigrants.

Menendez has hit back with ads of his own, attacking Hugin for profiting from price increases on drugs vital to cancer patients while at Celgene. The Democrat has also challenged Hugin's claims of being a moderate by pointing to his support for Trump, which included campaign contributions and serving as a Trump delegate at the Republican National Convention in 2016.

The Fairleigh Dickinson and Quinnipiac polls were released two days after a Stockton University poll showed a "statistical dead heat" between the candidates. The methodology of the Stockton poll was criticized, but some of its results share similarities with Fairleigh Dickinson's.

Besides the close overall contest, both polls released Wednesday found that nearly a fifth of likely voters were undecided or said they could change their minds by Election Day.

In the Fairleigh Dickinson poll, 22 percent of those voters were Democrats, compared with 6 percent of Republicans. Forty-two percent of independent likely voters said they haven't decided on a candidate yet.

“It’s both a blessing and a curse that a good number of Democrats remain up for grabs," Jenkins said. "Partisan leanings are usually a strong indicator of how someone will vote. If Menendez is able to capture the support of undecided Democrats, plus some of the independents, he will be able to decisively pull ahead of Hugin by November.

"It will be harder for Hugin to do the same," she added, "given the smaller base of undecided Republicans in the state."

With about 900,000 more registered Democrats than Republicans in New Jersey, Menendez has a built-in advantage over Hugin. Menendez is also expected to ramp up his advertising as the election nears, likely giving him a greater platform to continue to hammer the former Celgene executive over his leadership record and his connection to Trump.

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Trump is a "gift to Democratic candidates, including the incumbent senator," Jenkins said, because he remains deeply unpopular and 22 percent of likely voters who oppose him said they are undecided in the Senate race.

Mary Snow, a polling analyst at Quinnipiac, made a similar observation about Menendez.

"Also working to his advantage is that 63 percent of New Jersey voters want Congress to be more of a check on President Donald Trump," she said. "That number is even higher among women."

Kavanaugh and other New Jersey Democrats

The Quinnipiac University poll also asked likely voters about Judge Brett Kavanaugh and other New Jersey political figures.

The poll found that New Jersey voters say 59 percent to 35 percent that the U.S. Senate should not confirm Kavanaugh to the Supreme Court.

Women oppose his confirmation 65 percent to 28 percent, while men are opposed 51 percent to 42 percent. Republicans, however, support his confirmation 76 percent to 14 percent.

New Jersey voters approve 54 percent to 34 percent of the job Gov. Phil Murphy is doing and 58 percent to 37 percent of Sen. Cory Booker's performance. Both are Democrats.

Quinnipiac surveyed 1,058 likely New Jersey voters from Sept. 25 to Oct. 2. The poll had a margin of error of plus or minus 4.1 percentage points.

Fairleigh Dickinson's poll included 508 likely voters and had a margin of error of plus or minus 4.3 percentage points. It was conducted Sept. 26 to 30.

Email: racioppi@northjersey.com and pugliese@northjersey.com