(CNN) Former New York Mayor Michael Bloomberg plans to spend $100 million on an anti-Donald Trump ad blitz in key 2020 battleground states.

A Bloomberg spokesperson told CNN the digital campaign will target Arizona, Michigan, Pennsylvania and Wisconsin starting Friday and will run through the end of the primary season. The ads will not feature Bloomberg.

The ad blitz comes as Bloomberg is making moves toward a bid for the Democratic presidential nomination. Bloomberg has filed the necessary paperwork to get on the ballot in Alabama and Arkansas, but is not expected to be on the ballot in New Hampshire. Bloomberg has not announced a final decision on whether to enter the Democratic primary race.

"Mike believes that Trump is an existential threat to the country. He's not waiting to take on the President, he's starting now. This is all hands on deck," Bloomberg spokesman Jason Schechter told CNN.

Bloomberg's $100 million ad spend is a significant counterweight to Trump's fundraising machine.

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