00.  Washington D.C.; California (1974 only, due to redistricting type of race could not be determined); wrong district identified; no post IW
12.  Democratic incumbent running--Republican challenger
13.  Democratic incumbent--other challenger
14.  Democratic incumbent running--unopposed
19.  Democratic incumbent running--Republican challenger and others
21.  Republican incumbent running--Democratic challenger
23.  Republican incumbent--other challenger
24.  Republican incumbent running--unopposed
29.  Republican incumbent running--Democratic challenger and others
31.  Other incumbent running--Democratic challenger
32.  Other incumbent running--Republican challenger
34.  Other incumbent running--unopposed
35.  Other incumbent running--Democratic and Republican challengers
36.  Other incumbent running--Republican and other challengers
37.  Other incumbent running--Democratic and other challengers
39.  Other incumbent running -- Democratic, Republican, other challengers
40.  Democratic and Republican incumbents running--no other candidate (see note)
41.  Two Democratic incumbents running (see note)
45.  Two Republican incumbents running (see note)
49.  Democratic and Republican incumbents running--other candidate (see note)
51.  No incumbent Repr. running--Democratic candidate unopposed
52.  No incumbent Repr. running--Republican candidate unopposed
53.  No incumbent Repr. running--other candidate unopposed
55.  No incumbent Repr. running--Democratic and Republican candidates
56.  No incumbent Repr. running--Republican and other candidates
57.  No incumbent Repr. running--Democratic and other candidates
59.  No incumbent Repr. running--Democratic and Republican and other candidates
83.  No identifiable incumbent, Democratic cand in open race due to redistricting
84.  No identifiable incumbent, Republican cand in open race due to redistricting
85.  No identifiable incumbent, Dem and Rep cands in open race due to redistricting
89.  No identifiable incumbent, Dem, Rep and other cands in open race due to redistricting
99.  NA