Off the deep end.

Around the corner.

Way overboard.

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That's where you'll find the thinking of Robert Mueller and Democrats these days, according to talk-radio host Rush Limbaugh.

He unloaded Wednesday on special counsel Mueller -- who is supposed to be investigating claims of Trump campaign "collusion" with Russia -- for probing a wisecrack Trump made during the campaign.

Trump's Democratic opponent, Hillary Clinton, was in the midst of the huge scandal over the unsecured private email system through which she ran classified information while she was secretary of state under Barack Obama.

She had thousands of emails deleted and she couldn't find thousands more.

It was that scandal for which then-FBI Director James Comey cleared her of charges.

At the time, Trump cracked a joke about asking the Russians to hack Clinton's computers to reveal where her emails went.

And that's now a focus of Mueller's questioning, apparently.

"We know this because Rudy [Guiliani] granted an interview to Axios (a Millennial journalist enterprise) and you know what Mueller is interested in? You know what Mueller wanted answers to? When Trump cracked a joke, 'Hey, Russia! If you're listening, maybe you can find the emails that the media can't find of Hillary's – and if you do find 'em, hand 'em over.' A flat-out joke! He was mocking the fact that Hillary's emails were 'missing' and that nobody knew where they were – when, of course, Hillary knew where every damn one of them was because she was the one that deleted 'em and hid them!" Limbaugh said.

"This Mueller clown actually thinks that Trump was asking the Russians to hack Hillary's computers! This is beyond my ability to comprehend this. This culture, this society has lost all sense of any kind of adult sense of humor. It is just beyond me that this is actually what Mueller was focusing on in his written questions to the Trumpster. Holy smokes!"

Limbaugh was just getting warmed up about Mueller, whose nearly two years of investigation have produced no evidence so far of collusion on the part of the Trump campaign. It has, however, ignored much evidence that there was collusion between the Clinton campaign and Russians.

The "dossier" of unverified dirt on Trump, for example, was written by a former British spy with his own connections to Russia and funded by a company on the payroll of Clinton's campaign.

The Obama Justice Department and FBI presented the dossier to a secret court as evidence to obtain a warrant to spy on the Trump campaign.

"This guy Mueller is running around with preening arrogance thinking he's the most important savior of whatever the hell needs to be saved in Washington, ignoring crime after crime after crime after crime committed by Hillary Clinton and Comey and the Democrats and the FBI and the DOJ and everybody else tied to Obama! Just ignore all of that real collusion, real election rigging, and go looking after something that hasn't happened, didn't happen – therefore, cannot be found – that Trump supposedly did!" Limbaugh said.

"They put spies in his campaign! They were trying to find evidence! In fact, they were trying to coerce criminal activity among people in the Trump campaign by having FBI and CIA embedded spies! During the campaign. We haven't gotten a straight story about what really triggered the investigation in the first place," he said.

Limbaugh said a New York Times "supposed blockbuster story" about Trump wanting Hillary Clinton investigated was surreal.

"They should be! Especially Hillary Clinton should be! This thing going on with Mueller is one of the biggest travesties… in fact, it is. It is the biggest travesty of my lifetime, this entire thing," he said.

"I can't tell you the number of times over the course of my sterling broadcast career that I have cracked jokes and done bits exactly like [what Trump did]. Trump has this ability to mock his critics and to make fun of them and expose their phoniness and their lies, and I'll tell you this: I think some of these people really don’t get the humor.

"I think some of these numbskulls really do think that Trump was asking Russia to hack Hillary Clinton. When I saw that poll the other day from YouGov and The Economist, that 42 percent of the American people literally think the Russians tampered with ballots in 2016? Folks, do you know if that has happened, Trump would be in jail by now!"

He said it's a result of collusion between the establishment media in America and Democrats.

"They put the word 'collusion' out, and they still talk about this as though it happened when there's not a shred of evidence. It is bigger than a travesty. It is bigger than an outrage. I don't know the word to use to describe how ridiculous, dangerous, and whatever else this is."