NEW YORK - (AP) - A year after Mayor Michael Bloombergorchestrated a change to city law so he could run for a third term,voters decided Tuesday whether to keep the billionaire businessmanand richest man in New York City in office for another four years.

The founder of the financial information company Bloomberg LP ison track to spend more than $100 million on the most expensiveself-financed campaign in U.S. history, more than 10 times that ofhis challenger, Democratic city comptroller William Thompson Jr.

Although Bloomberg is favored to win Tuesday - recent polls havehad him up to 18 points ahead - his margin of victory is predictedto be far smaller than the near-20-point blowout he pulled off in2005.

Analysts say the smaller margin expected this year is partly dueto voter resentment over the way Bloomberg hastily persuaded theCity Council to change term-limit law last year so that he couldrun again. The anger is not widely predicted to boil up enough fora Thompson upset.

"The term limits thing did hurt - but the numbers still say'Bloomberg easy,"' said Maurice Carroll, Quinnipiac University'spolling director.

The former Republican mayor, not in any party but still runningon the GOP and Independence Party lines, had long insisted hesupported term limits before changing course last year.

New Yorkers who voted against Bloomberg Tuesday overwhelminglymentioned his changed position on term limits and exorbitantspending. He spent $85 million to win re-election in 2005.

Bloomberg would become the first three-term mayor in the citysince Democrat Ed Koch, who has endorsed Bloomberg.

Bloomberg and his supporters will be awaiting election results at the Midtown Sheridan. His opponent is expected to arrive at the New York Hilton & Towers in Manhattan after doing last-minute campaigning in the Bronx.

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