Local government elections in the western suburbs of Des Moines have often been sleepy affairs, with (mostly Republican) incumbents repeatedly coasting to re-election.

But big change is coming in two large suburbs, as every Republican city council member in Urbandale and West Des Moines has decided not to seek another term this November.

State Senator Matt McCoy announced yesterday that he will run for Polk County supervisor rather than for re-election to the Iowa legislature. His decision to challenge longtime Supervisor John Mauro in the Democratic primary sets up a “epic battle of the titans” in the fifth district, covering the south side of Des Moines, much of the city center and south of Grand areas on the west side. It also opens up Democratic-leaning Iowa Senate district 21.

Connie Ryan rolled out her candidacy yesterday but will likely have competition in the June 5 primary.