During his "My Take," Monday, "Varney & Co." host Stuart Varney reacted to Kamala Harris taking the lead over Donald Trump in 3 key states, arguing the former president is frustrated about Harris' growing popularity and for stealing his "no tax on tips" idea.

STUART VARNEY: Kamala Harris is on a roll. This honeymoon has legs. 

A New York Times poll shows the vice president leads by 4 points in 3 key states, Michigan, Pennsylvania and Wisconsin.

TRUMP, HARRIS IN DEAD HEAT IN POLL OF 7 CRITICAL BATTLEGROUND STATES

Worse, for Trump, according to a Financial Times poll, more people trust Harris on the economy. That had been his strong suit.

She is getting by with platitudes, vaguely saying she will "work for the working people," "make the economy work for everyone." 

No idea what that means in practice. 

She is flip-flopping on the border and on fracking, but at this point it doesn't matter. Harris is playing a wave of emotion. 

KAMALA HARRIS' LOW-MEDIA APPROACH MIRRORS BIDEN'S 2020 SUCCESS

The Democrats have found a new candidate who they think has a shot at winning.

They are not going to mess things up by doing press conferences or interviews with serious journalists. 

Besides, Harris will be crowned at next week's convention, and that should give her another lift.

By the way, look closely at her demeanor. The giggling, inappropriate laughter is gone. The rambling word salads, gone, because she never leaves her prompter. 

Her campaign has brought in some Obama people and they have improved her public performance. 

Trump is frustrated. He's arguing about crowd size, claiming her numbers are inflated by A.I. 

TRUMP EXPLAINS HOW HE WILL BRING DOWN PRICES, VOWS ‘NO TAX FOR SENIORS’ OR TIPS

He's miffed that Harris has taken over his "no tax on tips" idea. He's looking back to 2020, telling a big donor "we've got to stop the steal." 

This is according to the New York Times, which also reports he's used foul language to describe his opponent. 

It's not a good idea if you want to attract suburban women who can make or break his campaign.

Two weeks ago, it seemed the election was Trump's to lose. 

Now it seems he's got to fight to win, and he hasn't quite figured out how to do it.

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