One Trump aide described the environment as a "hurricane" and that the campaign was still determining the extent of the damage.
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Trump himself on Sunday morning lashed out at the Republicans defecting en masse from his campaign and warned of political retribution.
"So many self-righteous hypocrites," Trump tweeted. "Watch their poll numbers — and elections — go down!"
Talking points distributed to supporters and shared with NBC News emphasized that Trump "has been counted out many times in this election" and that his Republican critics "are more concerned with their political future than the future of their country."
But Trump has largely been left alone to carry that banner. Campaign manager Kellyanne Conway, normally Trump's go-to spokeswoman and his most prominent female advocate, dropped out of planned appearances on Sunday shows. So did RNC Chairman Reince Priebus, who issued a terse statement on Friday condemning Trump's 2005 comments immediately after they surfaced.
Campaign sources say Priebus met with Trump for about 90 minutes on Saturday and was "very frank" about the significant fallout from the story. The chairman's public silence has fostered speculation within the party that the GOP could cut off resources to Trump soon and focus on salvaging down ballot races.
"We're watching the end of the Trump campaign," one Republican state director told NBC News. "There is clearly no control over him inside the operation."
The state director added that Republican officials were waiting for word from the RNC on how to allocate their efforts in the final month.
According to a source within the RNC, Priebus is telling staffers to do "what's best" for them as aides at every level fear working on the Trump campaign's behalf could damage their reputation. Adding to their concern is the possibility more damaging footage of Trump might emerge.
"The guy has been in the public eye for thirty years," the source said of Trump. "There's got to be more."
RNC spokesman Sean Spicer denied Priebus had given staff permission to break with Trump,
that such reports were "100% false."
A source within the campaign also strongly implied to NBC News that Conway was considering leaving the campaign in the midst of the latest turmoil.
"Kellyanne is a good practicing Catholic," the source said. "She's thinking 'I have kids. Is this what I want?' She's never shied away from the role her faith plays in her life."
Conway told NBC News that any suggestions she was considering leaving the campaign were "a crock." She also told the
on Saturday she was not quitting the campaign and a photo on Sunday of her and Priebus flying with Trump to St. Louis for the debate.
Later Sunday, Conway tweeted another photo of herself and the candidate "in motorcade en route to flight to St. Louis for the debate," according to the tweet. Conway added that the photo was taken by Trump's, wife, Melania.
With Conway and Priebus off the Sunday shows, former New York City Mayor Rudy Giuliani made the rounds on Trump's behalf.
In contrast to Trump's defiant tone, Giuliani emphasized the nominee's contrition. But Giuliani also sheepishly conceded in multiple interviews that when the nominee bragged in the 2005 tape of using his celebrity status to grope women, he was describing sexual assault.
Giuliani also could not not say whether Trump followed through on his boast.
"I don't know how much he was exaggerating, I don't know how much is true, I certainly don't know the details of it," Giuliani told "Meet The Press" host Chuck Todd.
Highlighting another growing divide over messaging, Giuliani also said Trump would likely "not bring up Bill Clinton's personal life" in Sunday's debate even as Trump brought them up in a taped apology on Friday night and tweeted repeatedly about Juanita Broaddrick on Saturday and Sunday.
Giuliani added, however, that Trump might criticize Hillary Clinton's response to her husband's sex scandals.
Also on "Meet The Press," Giuliani insisted that Conway was still on board and that he had been chosen to represent Trump at the last minute because he was the only one "willing" to do so. But the relative silence from the Trump campaign, from running mate Mike Pence down, is dramatic.
Despite the latest difficulties, Trump advisers told NBC News the race is not lost and that the nominee can recover if he demonstrated true remorse, starting with Sunday's debate.
But even one of Trump's strongest campaign surrogates, Steve Cortes, acknowledged on Sunday that the episode had prompted supporters to reconsider backing Trump.
"Well look, I think everyone has to at least consider it, right, in a moment like this," Cortes said on Weekend Today. He added he had decided to stand by Trump's side.