Rep. Lois Capps's retirement will open up a Democratic-leaning seat.
Democrat Gary Kroeger, who starred in the early 1980s, will challenge GOP Rep. Rod Blum.
The Democratic Congressional Campaign Committee is running ads in the districts of four vulnerable House Republicans.
Scott Wong 04/06/15 04:06 PM EDT
J.D. Winteregg will try again to unseat Boehner who took 75 percent of the 2014 primary vote.
A young conservative upstart will challenge the embattled GOP representative in 2016.
Former Rep. Brad Scheider will seek to regain his old House seat in a rubber match.
Pete Gallego will again take on Rep. Will Hurd (R), who beat him in 2014.
Raja Krishnamoorthi, who lost to Duckworth in the Democratic primary in 2012, will run for the House again in 2016.
Congress typically is only in session four days a week.
The GOP dissenters included hard-line conservatives and centrists.