| Election Name: | 1918 Democratic Senate primary in South Carolina |
| Country: | South Carolina |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 1913 United States Senate election in South Carolina |
| Previous Year: | 1913 |
| Next Election: | 1924 United States Senate election in South Carolina |
| Next Year: | 1924 |
| Election Date: | August 27, 1918 |
| Image1: | Nathaniel B. Dial.jpg |
| Image1 Size: | x150px |
| Nominee1: | Nathaniel Dial |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 65,064 |
| Percentage1: | 58.70% |
| Image2 Size: | x150px |
| Nominee2: | Cole Blease |
| Party2: | Democratic Party (United States) |
| Popular Vote2: | 40,456 |
| Percentage2: | 36.50% |
| Map Size: | 180px |
| United States Senator | |
| Before Election: | Christie Benet |
| Before Party: | Democratic Party (United States) |
| After Election: | Nathaniel B. Dial |
| After Party: | Democratic Party (United States) |
The 1918 South Carolina United States Senate election was held on Tuesday, November 5, simultaneously with the special senate election to elect the United States Senator for a six-year term from South Carolina. Nathaniel B. Dial won the Democratic primary and was unopposed in the general election to win the six-year term to the Senate.
The primary election in 1918 for Senate was shaping up to be a contentious affair between Ben Tillman and Cole Blease, two of the state's most notorious demagogues. Blease had performed surprisingly well in the 1916 gubernatorial election where he had almost knocked off incumbent Governor Richard Irvine Manning III. The death of Tillman in July ended all prospects of an epic battle and the race became a contest between Blease and Nathaniel B. Dial. The South Carolina Democratic Party held the primary on August 27 and Dial garnered over 50% of the vote to avoid a runoff election. Blease suffered the worst loss of his political career mainly because of his vitriolic opposition to World War I which made him appear as a traitor. There was no opposition to the Democratic candidate in the general election so Dial was elected to a six-year term in the Senate.
| Democratic Primary | ||
|---|---|---|
| Candidate | Votes | % |
| 65,064 | 58.7 | |
| 40,456 | 36.5 | |
| James F. Rice | 5,317 | 4.8 |
|-| | colspan=5 |Democratic hold|-