In 2001, he outspent his Democratic opponent by 5 to 1, doling out $75 million of his own fortune.
In 2008, he changed the rules to run for a third-term, persuading the city council that the danger to democracy was outweighed by his urban leadership.
In 2009, he's spending $35,000 an hour, even though he holds a double-digit lead over Democratic city comptroller Bill Thompson in recent polls.
"How badly does Michael Bloomberg want a third term as mayor of New York?" crows NBC New York. "The billionaire is spending $35,000 an hour out of his own pocket."
Michael Bloomberg may spend $100 million during his campaign, already the most expensive self-financed bid in US history. The multi-billionaire owns 88 percent of Bloomberg, L.P., and is reportedly the richest man in New York City, with a net worth exceeding $17 billion.
Bloomberg is handily expected to win reelection. Comptroller Thompson has struggled to find his footing, overwhelmed by a sea of Bloomberg campaign ads. His "message has been drowned out by Bloomberg's barrage of advertising," NBC notes. "Polls show Bloomberg leading by 15 to 18 points."
How's New York responding to the news of Bloomberg's profligate spending? Fifty percent of those who responded to the NBC report online said they were "bored."
Spending his own money hasn't been the only kindling for critics' ire.
Earlier this year, Bloomberg took heat for videos produced by the city that demonstrated the ability of Americans in other states to buy unlicensed guns.
The videos showed violations of gun laws in Ohio, Tennessee and Nevada in a sting operation he authorized that cost city taxpayers $1.5 million and came weeks before his bid for re-election.
Bloomberg, who is the nominee of both the Republican and Independent Parties, hyped the sting on the liberal blog Huffington Post, hours before the videos were publicly available. Bloomberg said on the site that he authorized the investigation because the Bureau of Alcohol, Tobacco and Firearms reports that "89% of guns used in crimes in New York City last year originated out of state."