New York ? The four Democrats hoping to unseat Republican Mayor Michael Bloomberg met during their first debate Tuesday, using most of their time to criticize him rather than tussle with each other.

Political analysts say the candidates face a tough fight against the popular and billionaire incumbent, whose approval numbers continue to climb.

But repeatedly during the 90-minute debate, the Democrats bashed Bloomberg on every issue, from affordable housing to education to mass transit to rebuilding lower Manhattan.

On the panel were Fernando Ferrer, a former Bronx borough president; C. Virginia Fields, the Manhattan borough president; Anthony Weiner, a congressman from Brooklyn; and Gifford Miller, the City Council speaker.