(MCT) — The already volatile special election campaign to replace Jesse Jackson Jr. in Congress saw its biggest upheaval Sunday when state Sen. Toi Hutchinson dropped out and endorsed former state Rep. Robin Kelly in a move to unite against former U.S. Rep. Debbie Halvorson.

Hutchinson, of Olympia Fields, had been considered a top candidate along with Kelly, Halvorson and Chicago Ald. Anthony Beale, 9th, among what had been 16 candidates in the special Feb. 26 Democratic primary that will all but determine the next congressman due to the heavily Democratic nature of the 2nd Congressional District.