Billionaire American media mogul, Mr Michael Bloomberg, easily won the Republican primary, while two Democrats headed for a run-off in the New York mayoral contest, thrown into turmoil by the attacks on the World Trade Centre.
Further complicating the race was the possibility that Mayor Rudolph Giuliani may try to stay on to steer the city through its crisis.
With 26 per cent of the vote counted, the Bronx Borough President, Mr Fernando Ferrer, a Democrat, had 78,222 votes, or 36 per cent. Fellow Democrat and Public Advocate, Mr Mark Green won 69,222 votes, or 32 per cent. Candidates needed 40 per cent of the vote to avoid an October 11th run-off.
Mr Bloomberg, who has already spent more than $20 million of his own money on the race, easily defeated fellow Republican, Mr Herman Badillo, a former Congressman.
With 27 per cent of 5,630 precincts reporting, Mr Bloomberg had 11,168 votes, or 66 per cent, to Mr Badillo's 5,695 votes, or 34 per cent.
"This city is at a crossroads," Mr Bloomberg (59) told supporters.
"We weathered the crisis and now we face the rebuilding, an enterprise no city has ever dealt with before." The winners of each primary meet on November 6th.
The unofficial returns did not include write-in ballots, which will be counted later by the city Board of Elections.
Exit polling of Republican voters indicated that about 15 per cent wrote in a candidate's name - presumably Mr Giuliani - which is not enough to affect the primary's outcome. At least 15,000 absentee ballots will not be counted until in the week.
According to exit poll results, four in 10 Democratic voters and an overwhelming majority of Republicans said they would vote for Mr Giuliani in November if he sought a third term.