The 1988 United States Senate election in Delaware was held on November 8, 1988. Incumbent Republican U.S. Senator William Roth won re-election to a fourth term.
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Roth: 50–60% 60–70% 70–80% | |||||||||||||||||
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| Party | Candidate | Votes | % | |
|---|---|---|---|---|
| Democratic | S. B. Woo | 20,225 | 50.09 | |
| Democratic | Samuel Beard | 20,154 | 49.91 | |
| Total votes | 40,379 | 100.00 | ||
| Party | Candidate | Votes | % | ±% | |
|---|---|---|---|---|---|
| Republican | William V. Roth (Incumbent) | 151,115 | 62.06% | +6.89% | |
| Democratic | S.B. Woo | 92,378 | 37.94% | -6.27% | |
| Majority | 58,737 | 24.12% | +13.15% | ||
| Turnout | 243,493 | ||||
| Republican hold | Swing | ||||
