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Michael Bloomberg is living rent-free in Donald Trump's head

(CNN) Michael Bloomberg has spent more than $350 million of his own money on advertising in support of his 2020 presidential campaign. But President Donald Trump's now near-constant attacks on the former New York City mayor have given Bloomberg something no amount of money can buy: a growing sense that the incumbent is very, very worried about him.

Within 10 minutes on Thursday morning, Trump had sent out two tweets attacking Bloomberg for, among other things, his short stature and being a "mass of dead energy." Two days earlier, Trump had tweeted this about Bloomberg: "Mini Mike is a short ball (very) hitter. Tiny club head speed."

In the 13 days of February to date, Trump has sent at least eight tweets attacking Bloomberg, according to the invaluable Trump Twitter Archive. That represents a significant ramping-up of Bloomberg-dedicated tweets from Trump and far more than Trump has targeted anyone else in the Democratic field over that period of time.

Which is important! Because anyone who has followed Trump's campaign and presidency understands that his Twitter feed is the best window into what the President is thinking at any given moment. It's like being able to look into his mind and emotions -- constantly. So when Trump fixates on something or, in this case, someone, you know it's meaningful.

And Bloomberg, looking for ways to change the subject from his past support as mayor for the "stop and frisk" policing policy, smartly jumped on Trump's laser-like focus on him. At a campaign rally in North Carolina on Thursday, Bloomberg had this to say about being in the President's crosshairs (bolding is mine):

"Somebody said you know that he's taller than me, he calls me Little Mike and the answer is, Donald, where I come from we measure your height from the neck up. I am not afraid of Donald Trump. Donald Trump is afraid of us and that's why he keeps tweeting all the time. If he doesn't mention you, you've got a big problem. But the President attacked me again this morning on Twitter, thank you very much, Donald. He sees our poll numbers and I think it's fair to say he is scared because he knows I have the record and the resources to defeat him"

Bloomberg is right! Given that he has yet to appear in a single debate (he can't meet the previous donor qualifications since he is self-funding) and his name won't be on the ballot until March 3 (he made the strategic decision to skip the first four voting states), Bloomberg and his team have to be absolutely thrilled beyond words that Trump continues to attack and elevate him.

As I've noted before, Bloomberg is almost the perfect figure to get under Trump's skin. Both men are New Yorkers and both are rich. But Bloomberg actually spent more than a decade as the mayor of the city. And Bloomberg -- and this is the really important part -- is waaaaay richer than Trump, with an estimated net worth north of $60 billion. And unlike Trump, Bloomberg didn't inherit wealth, he created it for himself.

All of those things drive Trump batty. And Bloomberg knows it. Which is why he just keeps pouring it on -- millions more on TV ads, barbs thrown at Trump on social media, anything to provoke the President into responding. Which, of course, Trump can't help but do.

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