Thomas James Walsh (June 12, 1859 – March 2, 1933) was an American lawyer and Democratic Party politician from Helena, Montana who represented Montana in the US Senate from 1913 to 1933.
For his first two terms, he was elected by the state legislature, as was the custom of the time, and in 1924 and after he was elected by popular vote, which was established by constitutional amendment.
Walsh had a national reputation as a liberal but died before he could serve President-elect Franklin D.