State Senator John D. Sabini, a Queens Democrat, may find himself in the unusual position of losing the support of the Democratic organization in his borough in his bid for re-election, with leaders of the party likely to back City Councilman Hiram Monserrate instead. Democratic leaders in Queens are scheduled to meet on Monday to determine whether to endorse Mr. Sabini, who was first elected to the Senate in 2002. Normally, party organizations support incumbents, and Mr. Sabini is a former Democratic chairman in Queens. But Mr. Monserrate has put intense pressure on the party officials to gain their support...