Wearing a hard hat, Paladino made the pledge while standing with a few construction workers across the street from the World Trade Center site Wednesday.
He said if elected, he would use any legal means available to him to stop the construction of the mosque a couple blocks north of ground zero.
Paladino said there were "many, many alternatives'' to stopping the project, including "bleeding'' the developers "to death.''
The proposed Islamic community center has upset some relatives of Sept. 11 victims and led to nationwide demands that the project be moved. Supporters say it would be open to everyone, not only Muslims.