Julius Rockwell Whig Henry Wilson Know Nothing The 1855 United States Senate special election in Massachusetts was held during January 1855.

Henry Wilson was elected to fill the remainder of the term left vacant by the resignation of Edward Everett.

In 1854, the anti-immigration, anti-slavery American Party (better known as Know-Nothings) swept the Massachusetts elections, taking nearly every seat in the legislature.

On January 15, a printed circular called for a caucus of "all members in the House who believe in the freedom of debate, who refuse to sanction a high-handed course of political action, and who are opposed to the election of Hon.

Wilson joined Samuel Hoar's new anti-slavery Republican Party upon entering the Senate.