NEW YORK (NYTIMES) - Michael Bloomberg, the billionaire former mayor of New York City, spent at least US$30 million (S$41 million) on Friday (Nov 22) for a single week of television ads, a show of financial force that signals his willingness to use his vast personal fortune to reshape the Democratic presidential race.

The 60-second biographical commercials will begin on Monday in more than two dozen states and roughly 100 news media markets from California to Maine, a preview of a 2020 campaign budget that could easily stretch into the nine-figure range.

The scope of Bloomberg's ad buy is staggering. It is more than all of Bloomberg's potential rivals - other than the other billionaire running, Tom Steyer - have spent on television ads all year, and about double what Senator Cory Booker of New Jersey had raised in donations from February through the end of September.

"Mike is prepared to spend what it takes to defeat Donald Trump," said Howard Wolfson, a top adviser to Bloomberg, whose formal announcement of his candidacy appears imminent.

Rivals were quick to condemn Bloomberg, 77, for leveraging his personal fortune to sway the race.

"I'm disgusted by the idea that Michael Bloomberg or any other billionaire thinks they can circumvent the political process and spend tens of millions of dollars to buy our elections," Senator Bernie Sanders of Vermont said.

The new television campaign provides a hint of how Bloomberg will focus his resources beyond the early voting states. He will spend US$1.6 million in New York City, US$1.5 million in Los Angeles, US$1.2 million in Houston, US$1.1 million in Miami and US$794,000 in Boston in an eight-day period, according to Advertising Analytics, a media-tracking company. And more reservations were still arriving late Friday.

Bloomberg was not overlooking smaller states, either. He had booked US$52,000 in ads, for instance, in Fargo, North Dakota; and US$59,000 in Biloxi, Mississippi.

Bloomberg has not officially announced he is running for president, though this week he filed a formal "statement of candidacy" with the Federal Election Commission. He had previously filed to be on the ballot in three states.

His expected entry has injected a new element of uncertainty into the race, highlighting its fluidity as well as the angst among many moderate Democrats that the field has moved too far left, and that former Vice President Joe Biden, despite leading in most national polls, is poorly positioned to win. It has also stirred a debate among Democrats about the role of wealth in the primary and accusations from progressive rivals that Bloomberg is trying to buy the presidency.

"Swell," Steve Bullock, the governor of Montana who is running a shoestring campaign for president, wrote on Twitter on Friday. "Another Billionaire who thinks the Democratic nomination is for sale."