The right of senators accused of excessive expenditures in senatorial primary campaigns to hold their seats in the United States Senate has been challenged on two occasions in the past. In each of these cases the Senate held, by majority vote, that there had been no violation of law by the accused member and confirmed the validity of his election.
Charges of excessive expenditures in election campaigns have frequently been raised both in the United States and in foreign countries. In 1920 and again in 1924 contributions and expenditures in the presidential campaigns were investigated by special Senate committees following charges of the existence of huge slush funds for use in the interest of Republican candidates.
The two cases in which charges of excessive expenditures in senatorial primaries have been investigated and acted upon by the Senate in the past were those of Senator Isaac Stephenson of Wisconsin, whose seat was saved by a margin of two votes, and of Senator Truman H. Newberry of Michigan, whose seat was saved by a five vote margin, although he subsequently resigned as a result of the investigation.