Elections were held in 24 of the state senate's 50 districts.

The general election took place on October 9, 1877.

To claim control of the chamber from Republicans, the Democrats needed to net 16 Senate seats.

Republicans maintained control of the Iowa State Senate following the 1877 general election with the balance of power shifting to Republicans holding 38 seats and Democrats having 12 seats (a net gain of 2 seats for Democrats).

Source:[4] District boundaries in the Iowa Senate were redrawn before the 1877 general election.