There is considerable speculation that Essex County Democrats want Teresa Ruiz, a top aide to County Executive Joseph DiVincenzo and the party Vice Chairwoman, to run for the State Assembly next year — if they follow through on their threats to dump incumbent Wilfredo Caraballo in the 29th district. Caraballo created major political trouble for himself in June when he refused to join the rest of the Essex legislative delegation in backing Governor Jon Corzine over Assembly Speaker Joseph Roberts during the budget battle. Caraballo’s key political ally, Newark Democratic leader Stephen Adubato, Sr., had reportedly told Caraballo at the time that his actions could cost him party support when he seeks re-election in 2007. The 33-year-old Ruiz is considered one of the young rising stars in Adubato’s powerful North Ward political operation. She served briefly as the Essex County Democratic Chairman in 2003, between the resignation of Donald Payne and the election of Philip Thigpen. If Ruiz did go to Trenton, she would become the first Latina to represent Essex County in the Legislature.