The 1918 South Carolina United States Senate special election was held on November 5, 1918, simultaneously with the regular senate election to select the U.S. Senator from the state of South Carolina to serve the remainder of the term for the 65th Congress. The election resulted from the death of Senator Benjamin Tillman on July 3, 1918. William P. Pollock won the Democratic primary and was unopposed in the general election to win the remaining four months of the term.
The South Carolina Democratic Party held the primary on August 27 and William P. Pollock had a slight lead, but did not garner over 50% of the vote and was forced into a runoff election against Thomas H. Peeples. On September 10, Pollock won the runoff and was thereby elected for the short term in the Senate because there was no opposition to the Democratic candidate in the general election.
| Democratic Primary[1] | |||
|---|---|---|---|
| Candidate | Votes | % | |
| 38,816 | 34.9% | ||
| Thomas H. Peeples | 37,567 | 33.8% | |
| 34,807 | 31.3% | ||
| Democratic Primary Runoff[2] | ||||
|---|---|---|---|---|
| Candidate | Votes | % | ±% | |
| William P. Pollock | 49,920 | 62.4% | +27.5% | |
| Thomas H. Peeples | 30,044 | 37.6% | +3.8% | |
|-| | colspan=5 |Democratic hold|-