By Jenna Portnoy and Brent Johnson/The Star-Ledger

TRENTON — Not too long ago, Chris Christie was joking about it.

But as the controversy over lane closures at the George Washington Bridge continues to swirl, Democrats in Washington are pouncing on the Republican governor in the hope that they can stop his potential quest for the White House before it begins.

For Christie, it’s the first taste of what it’s like to be his party’s front-runner for the next presidential sweepstakes.

"National Democrats will make an issue about everything about me so get used to the new world, everybody," Christie said at a news conference Friday. "We’re not in Kansas anymore, Dorothy."

In Jersey’s form of Oz, the bizarre tale of September traffic jams and a supposedly punished small-town mayor makes the cable news. A group looking out for Hillary Clinton creates a graphic out of Christie’s unsmiling face, a picture of a bridge and a sign that reads: "Lane closed. Expect Christie?"

And the Democratic National Committee issues a campaign-style attack ad asking if the facts add up to "Chris Christie’s political payback?"

"When you run for president, you will be questioned about absolutely everything, and you can’t bluff your way past something like this. It’s not personal life or his weight; it’s related directly to his conduct in office," said Larry Sabato, director of the Center for Politics at the University of Virginia.

No one has publicly accused Christie of ordering two of his top appointees at the Port Authority of New York and New Jersey to close lanes to the world’s busiest bridge to get back at a Democratic mayor who wouldn’t endorse his re-election bid.

But questions about the incident have fueled a scandal that even Christie’s masterful team of brand managers can’t make go away.

Photos: Assembly transportation committee questions Port Authority executives 12-9-2013 29 Gallery: Photos: Assembly transportation committee questions Port Authority executives 12-9-2013

HURTFUL TOUGH TALK?

"One of the concerns voters will have about Christie is New Jersey’s reputation for rough, take-no-prisoners politics. It isn’t known as the Soprano State for nothing," Sabato said.

At first, the governor laughed off the insinuation he played a role in the traffic mess: "I worked the cones actually. Unbeknownst to everybody, I was actually the guy out there. I was in overalls and a hat, but I was the guy working the cones," Christie said, joking with reporters at a Statehouse news conference.

Last week, Christie was still trying to put the issue to rest. He said the resignations of his two top appointees to the Port Authority, Bill Baroni and David Wildstein, signaled a fresh start. He put former federal prosecutor Deborah Gramiccioni in Baroni’s place, saying: "We’re gonna turn the page now. We’re sending new leadership over there in Deb."

The governor went on to entertain reporters and people watching online — Statehouse news conferences are streamed live — for an hour, taking questions on every facet of the investigation.

"He wants to present himself as an independent and a tough executive," said Julian Zelizer, a professor of history and public affairs at Princeton University. "A lot of Democrats and a lot of Republicans want to present him as a real rough and unfair and somewhat explosive politician. It’ll be a competition between which story wins out."

DEMOCRATS DIG IN

The Democrats in Washington are using the tale of the bridge to undermine the narrative Team Christie perpetuated in all manner of media: He’s a bipartisan straight talker and principled leader. They’re eager to present the bridge controversy as part of a pattern, noting that Christie has given seemingly conflicting statements about whether he wants to extend in-state tuition to the children of people who came to this country illegally.

"This of course gives any political opposition that he has either now or in the future, fodder, which is exactly what he does not want," said Brigid Harrison, a professor of political science and law at Montclair State University. "He does not want questions raised about his qualifications or experience in office."

Just as Christie is flipping on the look-at-me national media switch, state Democrats appear to have finally found their mojo, landing punches on a governor who bobbed and weaved with ease during his first term.

"This is really in my view the first time that the Democrats have effectively held Christie’s toes to the fire," Harrison said. "In my view, this is a different Democratic Party than we’ve seen for the past four years."

Two public hearings gave Democrats in the Legislature more ammunition to keep the issue on front pages.

Next up? Documents from seven Port Authority officials are due on the desk of Assembly Transportation Committee Chairman John Wisniewski (D-Middlesex) on Thursday.

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