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 County results Griffin: 50-60% 60-70% 70-80% Williams: 40–50% 50–60% | |||||||||||||||||
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The1966 United States Senate elections in Michigan were held on November 7, 1966. IncumbentRepublican U.S. SenatorRobert P. Griffin, who had been appointed to the seat in May to fill the vacancy left by the death ofPatrick V. McNamara, was re-elected to a full term in office. Griffin defeated Democratic former GovernorG. Mennen Williams in the regularly scheduled election, as well as the concurrent special election to complete McNamara's unfinished term.
| Party | Candidate | Votes | % | |
|---|---|---|---|---|
| Democratic | G. Mennen Williams | 437,438 | 60.10% | |
| Democratic | Jerome P. Cavanagh | 290,465 | 39.90% | |
| Write-in | 2 | 0.00% | ||
| Total votes | 727,905 | 100.00% | ||
| Party | Candidate | Votes | % | |
|---|---|---|---|---|
| Republican | Robert P. Griffin (incumbent) | 1,363,530 | 55.90% | |
| Democratic | G. Mennen Williams | 1,069,484 | 43.85% | |
| Socialist Labor | James Sim | 6,166 | 0.25% | |
| Total votes | 2,439,180 | 100.00% | ||
| Party | Candidate | Votes | % | |
|---|---|---|---|---|
| Republican | Robert P. Griffin (incumbent) | 1,321,222 | 56.01% | |
| Democratic | G. Mennen Williams | 1,031,138 | 43.71% | |
| Socialist Labor | James Sim | 6,444 | 0.27% | |
| Total votes | 2,358,804 | 100.00% | ||
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