(CNN) Over the last 96 hours, we've learned that not only was campaign chairman Paul Manafort sharing polling with a Russian official linked to the country's intelligence service during the course of the 2016 campaign, but also that special counsel Robert Mueller's office spoke with Trump pollster Tony Fabrizio.

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"Mueller's team met with pollster Tony Fabrizio in February 2018, an interview that has not been previously reported and takes on new significance after Manafort's attorneys revealed Tuesday that Mueller's team is still interested in how Manafort shared polling data with his Russian intelligence-linked colleague.

"CNN journalists observed Fabrizio leaving the special counsel's office on the first of February last year and have since confirmed he was meeting with Mueller's team. At the time, the special counsel had been digging into Manafort's finances and political work ahead of his trial."

Big, big deal.

But wait, you say, we already knew Mueller was looking into the 2016 campaign and possible ties between it and Russia! And he already had people l ike George Papadopoulos and Michael Flynn admitting that they weren't totally honest in their testimony about the nature and breadth of their interactions with Russians! And we already knew that Manafort -- along with Donald Trump Jr. and Jared Kushner -- met with Russians including Natalia Veselnitskaya at Trump Tower in June 2016, a meeting that had been set up under the auspices that the Russians had dirt on Hillary Clinton!

And I will say that you are absolutely right! We did already know all of that!

But here's what President Donald Trump could say, roughly, before this week: There was never a whiff of collusion between the Russians and any serious person in my campaign. Most of these people who have pleaded guilty I have never heard of before. Manafort was the campaign chairman, yes, but everything he did wrong came long before he was affiliated with my campaign.

He just can't say that anymore. Not only do we know that Mueller knows Manafort was talking with -- and sharing polling data with -- Konstantin Kilimnik -- while he was the head of Trump's campaign, we also now know that Mueller has talked to the pollster from whom Manafort may well have taken those numbers that he shared with Kilimnik. (A source familiar with the situation told CNN that Fabrizio was unaware of what Manafort did with any and all polling data.)

Now, Trump said Thursday before he left for Texas that he "didn't know anything about" Manafort's dealing with Kilimnik -- or the fact that his campaign chairman shared polling data with the Russian. And there is no evidence yet public that Manafort ever told Trump that he was talking with Kilimnik, much less sharing poll numbers and discussing Ukraine and Russia.

And sharing poll numbers with a Russian isn't direct collusion -- although the timing of Manafort's conversations, which came shortly before Russia hacked into the Democratic National Committee servers and extracted emails that were eventually posted on the WikiLeaks website, is suspicious, to say the least.

The broader point here is that the news earlier this week about Manafort's conversations with Kilimnik changed the game. No longer is this about what Manafort did prior to ever even entering Trump's orbit. Now the conversation is about what Manafort did WHILE he was serving as the top official of Trump's campaign.

What the Fabrizio news does is make clear, again, a) how much more Mueller knows about all of this than we do, b) how long he has known (the special counsel team interviewed Fabrizio LAST February) and c) how deep and intertwined all of this is with Trump's top staff and aides.

Trump can continue to say that the Mueller probe is a hoax and a witch hunt. But the more we find out about what Mueller knows -- and has known -- the less credible that taunt from the President seems.