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Lieutenant Governor and Governor of Massachusetts (1916−1921)
Coolidge with his family (1900)
Coolidge entered the primary election for lieutenant governor and was nominated to run alongside gubernatorial candidate Samuel W. McCall. Coolidge was the leading vote-getter in the Republican primary, and balanced the Republican ticket by adding a western presence to McCall's eastern base of support.[51] McCall and Coolidge won the 1915 election to their respective one-year terms, with Coolidge defeating his opponent by more than 50,000 votes.[52]
In Massachusetts, the lieutenant governor does not preside over the state Senate, as is the case in many other states; nevertheless, as lieutenant governor, Coolidge was a deputy governor functioning as an administrative inspector and was a member of the governor's council. He was also chairman of the finance committee and the pardons committee.[53] As a full-time elected official, Coolidge discontinued his law practice in 1916, though his family continued to live in Northampton.[54] McCall and Coolidge were both reelected in 1916 and again in 1917. When McCall decided that he would not stand for a fourth term, Coolidge announced his intention to run for governor.