Iowa Senate districts following the 2012 redistricting.  Uploaded for use as a template for election result maps.  Party colors (Republican and Democratic) provided for the first two districts mentioned in the file.
http://www.legis.iowa.gov/Resources/Redist/redistricting.aspx (specifically http://www.legis.iowa.gov/DOCS/Resources/Redist/2011/2011-03-31/2013_Iowa_Senate.kmz)  Some formatting taken from File:2010 CA 19.svg by User:Haha169.
Iowa Legislative Services Agency