SPRINGFIELD — Lawyers for Illinois’ Democratic legislative leaders last week filed a motion to dismiss a lawsuit from Republicans and a Mexican American advocacy group regarding newly drawn legislative maps, calling the challenge “purely speculative” until full U.S. Census data is released.The motion, filed Friday, was an expected move following a July 14 status hearing for two consolidated lawsuits filed by Republican legislative leaders Sen. Dan McConchie, R-Hawthorn Woods, and Rep. Jim Durkin, R-Western Springs, as well …