President Donald Trump’s baseless claim that former President Barack Obama had tapped his phones during the election has been unraveling for so long now that it’s easy to lose sight of the fact that no Republicans of any stature remain willing to defend it — and that even Trump’s closest aides are twisting themselves into pretzels to avoid having to explicitly concede that their boss seems to have made the entire thing up.

In the past few days alone, White House spokesperson Sean Spicer used actual air quotes to suggest Trump hadn’t literally been talking about wiretapping — even though the president’s own tweets had literally been talking about wiretapping — while Trump adviser Kellyanne Conway hinted that the real culprits were tiny cameras hidden inside microwave ovens (prompting this gem of a sentence from the New York Times: “Ms. Conway clarified on Monday that she was not accusing the former president of snooping via a kitchen appliance”).

A pair of even bigger blows came on Wednesday. First, House Intelligence Committee Chair Devin Nunes — a devoted Trump ally and defender — flatly said that “clearly the president was wrong” if you take his tweets about Obama’s wiretapping “literally.”

“I don’t think there was an actual tap of Trump Tower,” Nunes said.

Next, embattled Attorney General Jeff Sessions, already under fire for misleading a Senate committee about his contacts with the Russian ambassador to the US, pushed back at his own boss when a reporter asked if he’d ever given Trump “reason to believe that he was wiretapped by the previous administration.”

“Look, the answer is no,” Sessions replied.

Bigger blows are still to come. On Monday, FBI Director James Comey will testify at a high-profile hearing about Russia’s interference in the presidential election. Comey has already made clear that he wants senior Justice Department officials to publicly repudiate Trump’s unfounded wiretapping claims. Democrats will happily give Comey the chance to do that himself next week.

Taken together, we’re at a truly remarkable moment for the young and deeply troubled Trump presidency. After first trying to avoid comment about his initial claim — one of the most incendiary charges in recent US political history — Trump’s own spokespeople are implicitly conceding that there’s no evidence to support his wiretapping allegation. Now some of the most powerful Republicans on Capitol Hill are saying that explicitly, and even Trump’s own attorney general is distancing himself from the claim as fast as he can.

Democrats have spent nearly two weeks questioning the veracity of Trump’s headline-grabbing shot at Obama. Republicans are now doing the same, which presents a new — and damaging — problem for a president who has had a difficult time gaining the acceptance and backing of the mainstream GOP members that he needs to enact his highly-conservative agenda.

Trump’s usual defenders are no longer defending the imaginary wiretap

It wasn't always this way. When Trump first made the wiretapping charge in a string of early-morning tweets earlier this month, a baffled White House quickly went into damage-control mode.

Spicer first said the White House was asking Congress to investigate the claim but would have no further comment, then said there was “no question that something happened” and that it was up to lawmakers like Nunes to sort out what that something was. Nunes said Trump had raised a “valid question,” and added, “I don’t think we should attack the president for tweeting.”

Conway tried to deflect blame from Trump by saying that he, as president, “has information and intelligence that the rest of us do not.”

Those defenses began to crumble as Obama and his former top aides angrily denied the accusations and Conway and other White House staffers were unable to provide any evidence to bolster Trump’s accusation. The Washington Post reported that the allegation seemed to originate from an unsourced Breitbart article circulating among top Trump aides titled “Mark Levin to Congress: Investigate Obama’s ‘Silent Coup’ vs. Trump.”

Democrats have spent weeks questioning the veracity of Trump’s shot at Obama. Republicans are now doing the same.

In recent days, Republicans have been trying to furiously distance themselves from Trump’s charge, with powerful GOP lawmakers like Arizona Sen. John McCain saying that Trump needs to either show some evidence or retract the charge. Asked by CNN’s Jake Tapper if he believed Trump, McCain said, “I have no reason to believe that the charge is true.”

Trump himself, unsurprisingly, seems to be doubling down on the falsehood. In an interview Wednesday with Tucker Carlson of Fox News, the president said, cryptically, “wiretap covers a lot of different things. I think you’re going to find some very interesting items coming to the forefront over the next two weeks.”

Still, it’s now been almost two weeks since the initial Trump tweets, and the White House has yet to publicize anything that would substantiate them. That leaves the president and his closest aides with two equally bad options: explicitly acknowledge that the claim was baseless, the opposite of what Trump seems inclined to do, or continue trying to subtly walk it back without formally retracting it. Either path would fuel new questions about Trump’s honesty and ability to distinguish fact from conspiracy theories propagated by fringe media outlets.

There’s a third possibility, and it could be the most damaging of all. It may well turn out that Trump was right that Trump Tower was bugged but profoundly and fundamentally wrong as to who did it, and why. It wouldn’t have been Obama. It would have been the FBI and other federal law enforcement agencies already investigating why so many of Trump’s closest aides were in direct contact with Russian intelligence officials in the run-up to the election.

We know there’s smoke when it comes to Trump’s ties to Moscow. Is there fire?

I noted last week that Trump’s invocation of Watergate in one of the tweets is instructive, though not in the way the president means. In the years after that scandal, Congress established an elaborate system of checks and balances specifically designed to prevent a president from being able to do what Trump is now alleging.

Under US law, the FBI or other intelligence agencies would need to get a warrant from a specialized surveillance court to eavesdrop on the calls, or read the emails, of an American citizen. That request would come from the FBI, not the White House, and would normally only be granted if the FISA Court had reason to suspect possible wrongdoing. (Though many critics note that it rubber stamps virtually all warrant requests.) And that’s where things truly get perilous for Trump.

We know, from a variety of news reports, that law enforcement and intelligence agencies have intercepted calls and other communications showing that members of the Trump campaign were in frequent contact with senior Russian intelligence officials. The FBI and other agencies continue to probe those interactions as part of a broader investigation into the Trump camp’s ties to the Russian government.

Those contacts, and Trump aides’ repeated lies about them, have led to a raging political feeding frenzy that brought about Flynn’s resignation and has prompted calls for Sessions to either step down — he’s already recused himself from the Russia probe — or appoint a special prosecutor.

If Trump was right about the wiretapping — a big and unlikely “if” — it wouldn’t have been at Obama’s direction, and it wouldn’t have been for political purposes. It would have been because there are real and lingering questions about Trump and Russia — and about whether close aides to a major party presidential candidate worked with a hostile foreign power to sway an election.

To summarize: Top Republicans on Capitol Hill say there’s no evidence to support Trump’s wiretapping allegation. The head of the FBI will soon have a chance to say publicly what he has said privately: that there’s no evidence to support Trump’s charge. The nation’s top law enforcement official, in other words, will have the chance to accuse the president he serves of lying. This is where we find ourselves less than two months into the Trump presidency.