In the immediate aftermath of their emphatic defeat in 2012, the monied mega-donors and professional operatives who run the GOP took solace in what then seemed like a dazzling, diverse roster of talented politicians and outsize personalities eminently equipped to lead the party out of the wilderness.

But after a brutal year of setbacks, scandals, and political floundering capped this month by a controversy that threatens to sink New Jersey Gov. Chris Christie's political career, the Republican establishment is warily scanning its bruised and bloodied field of potential 2016 standard-bearers — and many of the party poobahs are on the brink of panic.

In interviews with more than a dozen party officials, fundraisers, and strategists in New York and Washington over the past 10 days, Republicans described a palpable sense of anxiety gripping the GOP establishment in the wake of Christie's meltdown, and an emerging consensus that the once promising cast of candidates they were counting on to save the GOP from the tea party — and the nation from Hillary Clinton — is looking less formidable by the week.

Florida Sen. Marco Rubio — declared "The Republican Savior" on the cover of Time magazine last January — fell from grace after his attempt to pass comprehensive immigration reform, and his subsequent flip-flop on the bill, was met with revolt from the right, and a chorus of scorn from the left. Meanwhile, the establishment's other favorite son, Jeb Bush, virtually vanished after half-heartedly feeding the 2016 buzz during his short-lived book tour last spring. Since then, he has shown little interest in building a presidential campaign, and on Thursday his own mother said she hopes he doesn't run.

Now, with federal and local investigators digging into the George Washington Bridge scandal — an effort that will likely result in a subpoena for Bridget Kelly, the senior aide Christie fired for ordering the bridge closure, and the release of thousands more pages of internal documents — Christie's supporters are bracing for the worst.

"My sense is they're hoping against hope there aren't more shoes to drop," said Keith Appell, a Republican strategist with ties to the tea party who has been critical of Christie's moderate streak. "They really want to support him... but they can't control anything if another shoe drops."

A Republican operative at a large super PAC used the same metaphor — a favorite among political observers at the moment — to describe the unease in the party.

"Everyone thinks there's probably a 60% chance the other shoe will drop," said the operative, who like many of the people quoted in this story, requested anonymity to speak freely about a situation that is still evolving. "When I saw the press conference, I said, I don't think he's lying... But for the deputy chief of staff to do something like that requires a culture in the office that he would have set, and it probably requires other examples that would have made her feel like that was acceptable to do."

He added, "My gut is that they'll probably find something else."

For now, Christie is putting on a brave face as his team — and his most loyal supporters — attempt to present an image of strength and returning to business as usual. This weekend, Christie will embark on a two-day fundraising swing through Florida for the Republican Governors Association, where he just became chairman. Ken Langone, the billionaire co-founder of Home Depot who has been one of Christie's most enthusiastic boosters, insisted to the Washington Post that "enthusiasm among donors has never wavered."

Langone's sentiment was echoed by Ana Navarro, a Miami-based Republican strategist and pundit who is plugged in to the Florida fundraising scene. "Donors are calling around trying to get details and invitations," she said. "I think people are in a wait-and-see mode and in general like the way he has dealt with the issue in the last week... Donors are not fleeing form the guy like if he was radioactive material."

But behind the scenes, the situation is more tense. A Republican fundraising operative who has met with Christie said much of the interest he's seeing in the Florida fundraisers is being driven by donors' morbid curiosity — not solidarity with the governor.

"There are definitely people jumping ship," the operative said, noting that confidence in Christie's electability has dropped off sharply among the donors he's heard from.

And yet, without a clear, top-tier establishment alternative to hitch their wagon to, many donors are left with a menu of less-than-ideal options, ranging from right-wing firebrands like Texas Sen. Ted Cruz, to B-team governors like Scott Walker of Wisconsin or John Kasich of Ohio.

In fact, it's gotten so bad, the operative said, that some donors have started looking back fondly on the good old days of 2012: "You know what a lot of them say to me? I think we need Mitt back."

Of all the disappointments suffered this past year by the GOP elite, Christie's crisis came as the most startling. Many in the party establishment had come to rely on the governor's soaring approval ratings and landslide reelection to bolster their faith that — even after all the budget brinksmanship and government shutdowns — the party would eventually come around to the socially moderate, business-friendly, compromise-seeking brand of Republicanism that Christie represented. And as President Obama has struggled to implement his signature health care law, and seen his approval ratings crumble along the way, professional Republicans saw an opening for the Springsteen-singing, populist governor to reshape the electoral map.

But while Christie's base of Acela Republicans probably always had slightly inflated faith in his transformative abilities, they also grasp the implications of the current bridge scandal more acutely — and have responded more viscerally — than Republicans anywhere else in the country.

To a certain degree, savvy donors in the tri-state area recognize, and even admire, the hardball tactics Christie has been known to use. As one New York GOP operative put it, "Being on the wrong side of a political fight, you expect to pay some sort of consequence for it." But if there is one act of political retribution that crosses the line of propriety for Christie's donor base, it's shutting down the bridge that connects Manhattan to the New Jersey suburbs. (Indeed, of the 14 titans of industry and finance who confronted Christie at a private Park Avenue social club in 2012 to urge him to make a last-minute bid for the nomination, at least 10 own homes within five miles of the George Washington Bridge.)

"A lot of these guys live in Jersey and take that bridge to work in New York every day. Or a lot of them live in Manhattan and take it to go to a Jets game," said the operative of Christie's core network of donors. "The bridge in and of itself is always a disaster in terms of traffic. So adding to it purposefully and then bragging about it over email, I think, is what made it so stunning."

Road rage aside, many Republican elites now worry that the scandal will exacerbate the challenge for Christie to make his persona translate across time zones.

"The folks in New Jersey just have a different level of tolerance for power politics than other states," said the super PAC operative. "What's acceptable in New Jersey may be completely unacceptable in North Dakota, but may be several steps removed from Moscow."

Meanwhile, as the GOP establishment agonizes over whether Christie — or anyone — can emerge intact for the primaries next year, one piece of news this week did manage to calm some nerves: a report in Politico that Hillary Clinton keeps a political "hit list" of all those who have wronged her over the years.

As one veteran of the George H.W. Bush administration put it, "Bluntly, two misshapen psyches keeps you in the game."