Us Democratic presidential candidate Elizabeth Warren criticized billionaire Michael Bloomberg for spending $37 million on campaign ads on Monday, accusing the former New York City mayor of trying to buy off the results of the US election.

The 77-year-old media mogul Bloomberg officially announced on Sunday that he will run as a Democrat in the 2020 US presidential election, will use his amazing wealth to campaign and will not accept any donations.

Warren, a 70-year-old liberal senator from Massachusetts, is currently one of the leading Democratic candidates, according to opinion polls. Warren was criticized by Bloomberg for proposing a wealth tax on billionaires and often attacking corporate America.

At a campaign event in Iowa, Warren attacked Bloomberg's campaign strategy. "Michael Bloomberg is betting on democracy," she said. He doesn't need people, he just needs a lot of money. I think Michael Bloomberg is wrong. "

Mr. Bloomberg's campaign declined to comment on Mr. Warren's comments, but he defended his use of personal wealth at his first campaign in Norfolk, Va., on Monday.

"over the years, I have spent my resources on things that are important to me," Bloomberg said. I will give my reasons to let smart voters make their choices. "

Although Warren is currently ahead in the polls, moderates like Bloomberg worry that her proposed plans such as a wealth tax will alienate voters in swing states.