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Michael Bloomberg promised to spend big to beat President Trump this fall. Many Democrats say he hasn't lived up to that promise.

The former New York City mayor spent nearly $1 billion on his moderate bid for the Democratic nomination, but hasn't given a single dollar directly to Joe Biden's 2020 campaign. Yet he still managed to secure a speaking slot in the final night of the Democratic National Convention, and it has some Democrats questioning why, The New York Times reports.

Bloomberg's dollars bought him nothing but a miserable defeat in the Democratic primaries. He dropped out after a dismal Super Tuesday and threw his support behind Biden, leading some Democrats to believe he'd spend another billion on the former vice president's campaign, especially after it became clear Biden would be the nominee. He did transfer $18 million from his campaign to the Democratic party and said he'd spend another $50 million to help House Democrats. He also said he would pay his campaign staffers through Election Day so they could work in support of Biden.

But Bloomberg hasn't given to Biden's actual campaign, and he reneged on the pledge to his staffers. This led progressive activist Amy Siskind to ask the question:

Bloomberg's former national political chair Thomas Nutter told the Times that Democrats could expect "the re-emergence of the political Mike Bloomberg" come Thursday's DNC. He also said Bloomberg is "usually a later supporter," though University of Wisconsin-Madison political science professor Eleanor Neff Powell noted this year's emphasis on early voting means that may not be helpful. Read more at The New York Times.