Democrats sharpened their swords Sunday over the New Jersey bridge scandal, with one state lawmaker suggesting impeachment is an option for Gov. Chris Christie -- even as other prominent politicos said they were inclined to believe the governor's side of the story.

Christie on Thursday apologized for lane closures last fall that snarled traffic on the George Washington Bridge, after emails surfaced showing the closures were pushed by his associates as an apparent act of political revenge. The governor said he was "embarrassed" but insisted he had nothing to do with the incident.

The Republican governor, considered a possible 2016 presidential candidate, on Sunday earned the benefit of the doubt from some unexpected corners. Former Obama White House adviser David Plouffe, on ABC's "This Week," said his sense is Christie wouldn't have been so strong in his denials if he knew what was happening.

But New Jersey Assemblyman John Wisniewski, chairman of the legislative panel probing the closures, cast doubt on the governor's claims in an interview with Fox News. "It's hard to believe in the middle of a gubernatorial election that the governor didn't have a conversation with somebody on his senior staff about a big problem in Fort Lee," he said.

Further, Wisniewski charged that Christie "created the atmosphere that allowed this to start ... and to be covered up."

State Democrats are now considering new subpoenas as part of the closure probe. In a separate interview on CBS' "Face the Nation," Wisniewski was asked about the possibility of impeachment.

"The Assembly has the ability to do articles of impeachment," he said, suggesting that would be an option if it turns out Christie was involved in a cover-up. However, Wisniewski added: "We're way ahead of that, though."

The lawmaker acknowledged that officials have found no "direct communication" tying Christie to the scandal, but repeatedly challenged the notion that his deputy chief of staff -- whom Christie fired for her role in the closures -- did not loop him in.

"It's unbelievable," he said.

On the same program, Rep. Elijah Cummings, D-Md., top Democrat on the U.S. House oversight panel, indicated Congress could get involved. "We'll look into it if it comes to us," he said.

But others either defended Christie or declined to speculate on whether he was involved -- allegedly, the lanes were closed as payback over a decision by Fort Lee's mayor not to endorse him for reelection last year.

"[Christie has] held people accountable, he fired people, and I think ... it is a very big difference than how this administration has handled a lot of things that have happened; whether it's IRS, whether it's Benghazi," Rep. Adam Kinzinger, R-Ill., said on ABC's "This Week."

Even Christie's possible 2016 competitors declined to take a shot at him.

On the Republican side, Sen. Marco Rubio, R-Fla., said on "Face the Nation" that he didn't have much to add when asked about the Christie scandal.

On the Democratic side, Maryland Gov. Martin O'Malley gave a similar response when asked on CNN's "State of the Union."

Fox News contributor George Will said Sunday that if what Christie said Thursday is true, the political damage will be minimal. In a political world dominated by "synthetic figures," he said on "Fox News Sunday," Christie "has established his authenticity."