Her Republican opponent branded her "Montclair Mikie" Sherrill, which is shorthand for left-wing firebrand whose views are out of step with the 11th Congressional District.

But Sherrill unveiled a new persona on Wednesday night's debate stage: "Moderate Mikie."

Sherrill, a former U.S. Navy pilot who became a federal prosecutor, used her first televised debate with Republican legislator Jay Webber as a chance to prove to the voters in the historically Republican district that she is no fire-breathing liberal of the Bernie Sanders-Elizabeth Warren ilk.

Webber, too, used the NJTV-sponsored debate to introduce himself as a sensible, moderate Republican, cut more in the mold of outgoing veteran Rodney Frelinghuysen — a Chamber of Commerce Republican, not the out-of-the-mainstream conservative he's often depicted to be.

The normally sedate and overlooked 11th District has suddenly found itself a prime target for national Democrats in their quest to reclaim the House in the midterm elections.

The Democrats need a net gain of 23 seats on Nov. 6, and the 11th is among four potential takeover targets in New Jersey and potentially the most prized — it has been a Republican redoubt in the Northeast since the 1980s, when redistricting shifted its base from Essex to Morris counties.

Frelinghuysen, a scion of a New Jersey dynasty dating back to the Revolutionary War, won the seat in 1994 and cruised to large, double-digit wins since.

But in recent years, Democratic registration has grown as a rapid clip — the Republican advantage has shrunk to 7,200, less than half of what it was in 2016. That same year, Trump carried the district by only one point. And since his election, Trump has done little to reverse that tide — the district is deeply divided over his presidency, and there is little to suggest that anybody is going to change the voters' minds over the next four weeks.

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For Sherrill, a newcomer to politics, the 11th has proved to be a tricky terrain. She is seen as a progressive, but appears wary of carrying the "Trump resistance" banner into the fray. At Wednesday's debate, Sherrill was determined to show she is more Morris Plains than Montclair.

There were no heated vows to fight Trump, even though being "appalled" by the president was what motivated her to run in the first place. The Nov. 6 midterms loom as a referendum on Trump's presidency, but you would never have guessed that watching Wednesday's contest.

Sherrill repeatedly promised to be bipartisan — a far cry from the combative, confrontational tone that many in the party's grass roots are demanding.

On tax policy she sounded more centrist Republican than mainstream liberal Democrat, and she refused to endorse issues like free community college tuition, which has become a popular talking point for Democrats and was launched by Gov. Phil Murphy this summer.

"Without understanding how that would be paid for, I haven't supported it because it sounds like it would raise taxes on our families,'' she said.

The moderate tone puzzled some of her ardent "resistance" activists who mobilized around her candidacy.

For Eric Fritsch, 32, a Teamster for the film and television industry from West Orange, it was jarring to hear Sherrill oppose Democratic Party wish-list items like free community college tuition or "Medicare-for-all" coverage out of fear that it may raise taxes. She used the same excuse to sidestep supporting a "carbon tax" to reduce global warming.

"By going on the defensive about taxes ... she is accepting a Republican framing that we don't want to be responsible with taxes in the first place,'' said Fritsch, who insisted that he remains a "very enthusiastic" Sherrill supporter.

But to others, Sherrill was taking a sensible, strategic position in the late stage of the race. In a recent Monmouth University poll, Sherrill holds a 48 percent to 44 percent lead among likely voters using a standard turnout model for midterm elections. That's a statistically insignificant lead when the poll's margin of error is considered.

The poll also said the race is basically at the same place as it was in June, only this time there are fewer undecided voters, about 6 percent, up for grabs. District voters are equally divided in their feelings about Donald Trump (48 percent approve of Trump compared with 49 percent who disapprove) and the recent confirmation battle over Supreme Court Associate Justice Brett Kavanaugh did little to change that sentiment.

In effect, the polling suggests that most voters have already made up their mind about Trump. A hard-line attack on Trump is not going to win over many converts and may only do Sherrill more damage in the final homestretch of the race, argues Patrick Murray, the Monmouth University pollster.

Murray said Sherrill runs the risk of "sending a signal to some of those moderate Republicans who are comfortable with her on a whole host of issues and don't see her as a partisan firebrand ... that she will be one of those Democrats that, once they get into office, they are going to toe the party line and score political points."

Webber also seemed motivated to reassure moderates. The Harvard-trained lawyer is one of the Legislature's most staunch conservatives and has earned the blessing of Trump, which he sent via a tweet last week.

Yet in the debate, Webber was far from a "Make American Great Again" acolyte vowing undying loyalty to Trump. In short, he was casting himself as a descendant of Frelinghuysen's moderate stewardship.

He barely mentioned Trump, although he generally praised the Trump-signed tax overhaul as an economic stimulant, praised Trump's handling of the military, and promised to parlay Trump's endorsement into a meeting — and hopefully a commitment — on the proposed Gateway train tunnel project.

"And I will take that [endorsement] and go to the White House and say, 'If you want to work with us, Mr. President, you have to treat New Jersey well. This is a top priority for our district,' '' Webber said.

Webber's promised sit-down is predicated on his winning. Right now, the district is listed as "leans Democratic" by the Cook Political Report, a non-partisan handicapper of congressional races based in Washington, D.C.

Sherrill has hefty cash advantage, having raised about $4.2 million with nearly $2.9 million left on hand, compared with Webber's $574,000 raised. He has $172,000 on hand, according to most recent campaign finance filings.

And, for now, Sherrill has grass-roots supporters like Fritsch who are willing to look the other way when Sherrill veers to the middle.

"I recognize that the 11th District isn't just Montclair and West Orange,'' Fritsch said, referring to the liberal bastions in the district. "It's also further west towns. I understand that she has to be a candidate and representative for the entire district. That doesn't mean that I don't personally wish for more."