NEW YORK - New York Democrats on Tuesday are choosing their candidate to succeed Mayor Michael Bloomberg in a primary election that has featured a scandal over lewd pictures, an accusation of racism, a council leader vying to be the city's first female, openly gay mayor and a see-sawing list of front runners.
Bill de Blasio, the city's public advocate, has taken the lead, but he may not have the 40 per cent needed to avoid a run-off. His rivals, City Council Speaker Christine Quinn and Bill Thompson, are competing for second place.
Polls opened at 6 a.m. (1000 GMT) across New York, the biggest US city.
Two polls on Monday showed De Blasio with a comfortable lead. A Quinnipiac poll put his support at 39 per cent, while an NBC 4 New York/Wall Street Journal/Marist poll found him the choice of 36 per cent of likely voters.
"Remember that there are no undecided voters on Election Day," said Maurice Carroll, director of the Quinnipiac University Polling Institute. "If de Blasio picks up just a few of those undecided voters, he's over the top."
In the same arena, former Congressman Anthony Weiner is fighting for his political life.
Weiner resigned from Congress in 2011 after admitting that he had sent lewd pictures of himself to women he met online and then lied about it.
When he announced his candidacy for mayor, he asked voters to give him a second chance, and he quickly moved to the top of polls. But campaign issues like police tactics and housing were overshadowed by another scandal involving lewd photographs he sent online, and his campaign began to sputter.
As the clock ticked down to Tuesday's primary election, New York magazine published an interview with Bloomberg in which he effectively threw his support behind his close ally, Quinn.
Bloomberg criticised de Blasio for his campaign's emphasis on economic inequality. But he took particular issue with the prominent role de Blasio's mixed-race family has played in the campaign, suggesting the strategy was meant to fuel "class warfare" and was potentially "racist."
The Republican contest, which has been tame in comparison with the Democratic race, will see Joe Lhota, the former head of the city's mass transit agency, and billionaire businessman John Catsimatidis face off in Tuesday's Republican primary.
Regardless of who wins in November's general election, the next mayor will inherit a city whose nearly 300,000 teachers, firefighters, police and other public service employees are working under expired contracts.
The more than 100 municipal contracts expired at least a year ago, leaving the city with a bill for retroactive pay increases that may top $7 billion.
Like the last mayor, the next one will also have to close a budget gap: The city is running a deficit of about $2 billion going into fiscal 2015, which begins on July 1.