In the 1879 Iowa State Senate elections Iowa voters elected state senators to serve in the eighteenth Iowa General Assembly. Elections were held in 29 of the state senate's 50 districts. State senators serve four-year terms in the Iowa State Senate. The general election took place on October 14, 1879. Following the previous election, Republicans had control of the Iowa Senate with 38 seats to Democrats' 12 seats. To claim control of the chamber from Republicans, the Democrats needed to net 14 Senate seats.