The former New York City mayor, who became a Democrat just last year, filed paperwork with the Federal Election Commission on Thursday to formally create a presidential campaign committee. The move legally allows him to begin raising and spending money on a 2020 campaign, although his team says he’s yet to make a final decision.

A formal announcement is expected in the coming days.

The 77-year-old Bloomberg is one of the richest people in the world. His estimated net worth exceeds $50 billion, and he’s already committed to spending more than $100 million to help defeat President Donald Trump in 2020 whether he runs or not.

Bloomberg’s enormous wealth, his ties to Wall Street, and his status as a former Republican could make it difficult for him to win support among traditional Democratic primary voters. Should he run, his advisers have charted an unconventional strategy that calls for him to bypass the first four states on the primary calendar and make an aggressive play for the so-called Super Tuesday states that vote in early March.

Before Thursday’s federal filing, he had already filed paperwork to qualify for presidential primary ballots in three states.

Bloomberg’s team says he’s stepping toward a run because of the perceived weakness at the top of the current Democratic field, particularly in establishment-favorite former Vice President Joe Biden’s candidacy.

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