1978Final results
1978 election for U.S. Senate in Maine
U.S. Senate · Maine
William Cohen (R) won with 56.6% of the vote, defeating William D. Hathaway (D) by 22.7 points.
William CohenRepublican · winner
56.6%212,294
William D. HathawayDemocrat
33.9%127,327
Hayes E. GahaganIndependent
7.4%27,824
John J. JannaceIndependent
1.5%5,553
Plato TrumanIndependent
0.6%2,116
375,114 votes
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
The seat over time
D − R margin in this seat's races around 1978
Races before and after
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
The candidates
William Cohen (R)William D. Hathaway (D)Hayes E. Gahagan (I)
Also on the ballot: John J. Jannace (Independent), 1.5%; Plato Truman (Independent), 0.6%