State Sen. Iris Martinez will replace Dorothy A. Brown as Cook County Circuit Court Clerk next month, after winning her election Tuesday.Unofficial results show Martinez had received 70% of the vote at the time she declared victory.Martinez, a Democrat who has represented Illinois’ 20th Senate District on the Northwest Side since 2003, will be the first Latina to hold the position of clerk.Brown did not seek a sixth term as circuit clerk.Martinez’s campaign promised to modernize the technology used in the clerk’s office …