Considering that New Jersey has about 700,000 more registered Democrats than Republicans, and that the state hasn't elected a Republican to the U.S. Senate since 1972, you might expect incumbent Sen. Cory Booker (D-NJ) to have a huge lead over his GOP opponent -- but the race is tighter than many thought.

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That's according to a new Fairleigh Dickinson University PublicMind poll out Wednesday, which weighs the celebrity status and 1.4 million Twitter followers of Booker against the relative anonymity of Republican challenger Jeff Bell.

"Just 13 points separate Cory Booker from Jeff Bell in the upcoming Senate election," said Krista Jenkins, professor of political science and director of PublicMind at FDU, citing the current 42-to-29 percent split among decided voters. "The fact that he (Bell) trails an incumbent senator with rock star appeal by such a margin that many would have expected to be larger suggests that anti-incumbency is helping to define this election."

In this particular race, 27 percent of likely voters remain undecided, with about two months to go until the election.

Registered New Jersey voters certainly are not happy with the incumbent commander in chief, according to the survey. Just over a third (36 percent) approve of President Barack Obama, while 49 percent said they disapprove. Of those who back the president, 78 percent said they would vote for Booker, a fellow Democrat.

The majority of Garden State residents also said the country is on the wrong track. Fifty-five percent said they are pessimistic about the direction in which the country is headed. Just 31 percent expressed optimism.

Without mentioning specific candidates, the survey also asked voters if they plan to support a Republican or a Democrat in their congressional district. Voters are evenly divided, with 35 percent saying they will back a Democrat while 34 percent intend to vote for a Republican candidate. In June, Democrats had an 11-point edge over Republicans.

"That gap from a few months ago is now gone," Jenkins said, "a sign, perhaps, of the continued frustration voters feel with Obama's leadership that's trickling down to Democratic candidates."

In November, New Jersey voters will also be asked if they'd like to amend the state constitution to allow judges to deny bail for dangerous criminals. The poll surveyed Garden State residents on that issue as well, and a vast majority (77 percent) said they will support the ballot question.