| Election Name: | 1936 United States Senate election in Massachusetts |
| Country: | Massachusetts |
| Flag Year: | 1908 |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 1930 United States Senate election in Massachusetts |
| Previous Year: | 1930 |
| Next Election: | 1942 United States Senate election in Massachusetts |
| Next Year: | 1942 |
| Election Date: | November 3, 1936 |
| Image1: | File:1935 Henry Cabot Lodge Jr Massachusetts House of Representatives.png |
| Nominee1: | Henry Cabot Lodge Jr. |
| Party1: | Republican Party (US) |
| Popular Vote1: | 875,160 |
| Percentage1: | 48.53% |
| Party2: | Democratic Party (US) |
| Popular Vote2: | 739,751 |
| Percentage2: | 41.02% |
| Map Size: | 300px |
| Image3: | File:Thomas C. O'Brien (1).jpg |
| Party3: | Union Party (US) |
| Popular Vote3: | 134,245 |
| Percentage3: | 7.44% |
| U.S. Senator | |
| Before Party: | Democratic Party (US) |
| After Party: | Republican Party (US) |
The 1936 United States Senate election in Massachusetts was held on November 3. Incumbent Democratic Senator Marcus A. Coolidge declined to stand for re-election. Republican Henry Cabot Lodge Jr. won the race to succeed him over Democratic Boston mayor James Michael Curley and former Suffolk County prosecutor Thomas C. O'Brien.
The election was notable because although Democrats expanded their overall Senate majority to 74 seats, Massachusetts was the only seat gained by Republicans. Curley's campaign may have been damaged by President Roosevelt's decision to remain aloof and the candidacy of O'Brien, who siphoned many usually Democratic Irish-American votes in Boston.
At the Springfield convention, held June 18–21, the fight between Lodge and Weeks came to a head. Observers considered the race the closest of any in the state and both candidates claimed a substantial lead in delegates. James Cavanaugh, by then a decided third, declared that he would not throw his delegates to Weeks in the event of a second ballot, but did not say he would throw them to Lodge.
Weeks received a major boost on the third day, when his candidacy was backed by Joseph W. Martin and John W. Haigis, the candidate for Governor.[3]
The voting itself was not decided until the final state senate district, the Worcester and Hampden district, declared its vote. Although it was a Weeks district, Lodge needed only six of its votes, which he secured about halfway through the roll call.[4]
After the voting concluded, Weeks took the podium to make the endorsement unanimous and give his personal support to Lodge.[4]
All three losing candidates entered the general election as the nominees of third parties. Cook ran on an "Economy" ticket, Gray ran on the Social Justice ticket, and O'Brien ran on the national Union Party ticket.
The Democratic nominee was Governor and former (and future) Mayor of Boston James Michael Curley. President Franklin Roosevelt declined to endorse Curley, which may have affected the final results.
Lodge was highly critical of Curley's tenure as Governor, but did not mention him by name. Curley resorted to personal attacks, referring to Lodge, who was only 34 years old, as "Little Boy Blue" and "a young man who parts both his hair and his name in the middle." He accused Lodge of being a reactionary in the supposed mold of his grandfather, Henry Cabot Lodge. Lodge criticized Curley for his failure to achieve federal funding for Massachusetts during the Great Depression, which may have been the result of Curley's personal feud with President Roosevelt. He defended his own record as supportive of labor and economic intervention and his grandfather's as protective of the laboring classes via restriction on immigration and opposition to international adventurism.
O'Brien, who ran at the urging of Charles Coughlin, campaigned for the urban Irish Catholic vote. His campaign was spurred by Curley's efforts to align with President Roosevelt, from whom Coughlin had broken earlier in his term.
Roosevelt made a personal swing through the state as part of his re-election campaign, but when Curley tried to get a photograph with Roosevelt, he made a point of turning away.
Later in the race, Curley tried to have Lodge's name removed from the ballot by arguing, through his political ally and Lodge's primary opponent Alonzo B. Cook, that "Jr." was reserved for the son of a man with the same name, and Lodge was instead the grandson. This controversy was quashed when Lodge produced a birth certificate reading "Jr." In fact, Curley's own legal name did not include "Michael", but he was listed on the ballot as "James Michael Curley" nonetheless. The Lodge campaign did not challenge this discrepancy.