TRENTON - Even as Gov. Christie cruised to a landslide 22-point reelection in November 2013, some in his party complained that he had failed to help the GOP make gains in the Democratic-controlled Legislature.

Christie, a Republican preparing to run for president in 2016, then tried to oust Senate Minority Leader Thomas H. Kean Jr. (R., Union), who led the Senate GOP's election efforts, from his leadership post and round up votes for a closer ally, Sen. Kevin O'Toole (R., Passaic).

The move failed and resulted in an embarrassing public rift between Christie and his mentor, Kean's father, former Gov. Thomas H. Kean Sr.

So it was notable Monday when the younger Kean stood on the Senate floor to oppose Democrats' attempt to override Christie's controversial veto of legislation to overhaul the Port Authority of New York and New Jersey. Kean proposed a compromise measure.

"How ironic is it," Sen. Joe Kyrillos (R., Monmouth) said on the floor, that it was Kean "leading the charge" against the override. "You all know what I mean," he said.

Kyrillos, who was once close to Christie but now says he may support Jeb Bush in 2016, said he was "dying" to vote for the override, but preferred Kean's alternative.

Kean said Tuesday that his spat with Christie was "ancient history."

He said he got involved in the Port Authority issue "because I realized three months ago there was going to be an impasse." He sought to reconcile the most "workable provisions" of a proposal by Christie and New York Gov. Andrew Cuomo, and the measure that passed both state legislatures last year.

The New York and New Jersey legislatures unanimously passed identical bills that sought to increase transparency and accountability at the Port Authority, including establishing an Office of the Inspector General and requiring frequent audits.

Christie and Cuomo, a Democrat, announced in December they would veto the measure and offered an alternative.

Kean said that proposal gained no traction among legislators.

The bistate authority, which operates airports, bridges, and tunnels, drew scrutiny after passing massive toll increases in 2011, and again last year because of the George Washington Bridge lane-closure scandal.

Statehouse observers said Kean's move was less an embrace of Christie than a way to protect his caucus, which was vulnerable to charges of hypocrisy after initially supporting the Democrats' bill.

(In a separate vote Monday, Kean voted against Christie's controversial nominee for the Pinelands Commission.)

Analysts said Kean's proposal also plots a potential path forward to reforming the Port Authority, which is universally reviled in Trenton, and denies a political win to Senate President Stephen Sweeney, the Democrat who hopes to succeed Christie as governor in 2017.

"Tom Kean's capacity for forgiveness is pretty remarkable," said Carl Golden, a political analyst at Stockton College and former press secretary to Kean's father and Gov. Christie Whitman.

Golden said some Senate Republicans were anxious about the override vote, given the Port Authority problems exposed by the bridge scandal.

"Tom Kean found them a way out," he said, offering his colleagues "a very solid fallback position."

Now Democrats are in "a bit of a bind," Golden added, because "they went for an all-or-nothing, knowing it was going to fail."

On Tuesday, Democrats held a news conference to call on the Port Authority to sell its non-transportation real estate assets, such as the World Trade Center, and dedicate the proceeds to the Gateway rail tunnel to Manhattan.

Kean said his legislation proposed selling those assets in an efficient manner, a "key provision" not in the Democrats' bill.

Democrats argued that Kean's bill would weaken legislative oversight and require fewer audits than their proposal.

O'Toole, to be sure, remains Christie's top lieutenant in the Senate and his fiercest defender. He repeatedly assailed Democrats for running what he called a partisan investigation into the September 2013 lane closures.

On Monday, O'Toole took to Christie's defense in the administration's latest controversy: a $225 million settlement with Exxon over decades of pollution in North Jersey.

State prosecutors had sought $8.9 billion in damages at trial last year, after 10 years of litigation.

Democrats in the Senate passed a resolution Monday expressing opposition to the settlement, saying it was insufficient. Once published in the New Jersey Register, the settlement will be open to public comment for 30 days and must be approved by a Superior Court judge.

Before the vote, O'Toole said it would be inappropriate for the Legislature to intervene in "an open, pending matter."

He warned that the resolution could expose the Legislature to charges of ethics violations.

The two episodes illustrated the contrast between two of the Senate's most prominent Republicans: Kean as a statesman, in the mold of his father, and O'Toole as an attack dog, lashing out at the governor's detractors.

So on an issue in which Democrats and Republicans share a common goal - overhauling the Port Authority - "Kean was the appropriate choice and the right choice to make this play," Golden said.

Patrick Murray, director of the Monmouth University Polling Institute, said Kean "was bloodied and battered by the leadership fight" with Christie.

"We didn't see him as a significant, strong presence publicly. I think he's found a way to assert himself here, and find an angle," Murray said.