| Election Name: | 2001 Massachusetts's 9th congressional district special election |
| Country: | Massachusetts |
| Type: | by-election |
| Ongoing: | no |
| Previous Election: | 2000 United States House of Representatives elections in Massachusetts#District 9 |
| Previous Year: | 2000 |
| Next Election: | 2002 United States House of Representatives elections in Massachusetts#District 9 |
| Next Year: | 2002 |
| Seats For Election: | Massachusetts's 9th congressional district |
| Election Date: | October 16, 2001 |
| Image1: | Stephen F. Lynch, 2005.jpg |
| Nominee1: | Stephen F. Lynch |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 44,943 |
| Percentage1: | 64.97% |
| Party2: | Republican Party (United States) |
| Popular Vote2: | 22,645 |
| Percentage2: | 32.73% |
| Map Size: | 250px |
| U.S. Representative | |
| Before Election: | Joe Moakley |
| Before Party: | Democratic Party (United States) |
| After Election: | Stephen F. Lynch |
| After Party: | Democratic Party (United States) |
Massachusetts's 9th congressional district special election of 2001 was held in the U.S. state on October 16, 2001, to fill the vacancy caused by the death of Representative Joe Moakley. Democratic State Senator Stephen F. Lynch won the election; defeating six candidates in the Democratic primary and three in the general election.
The Democratic and Republican primaries were held on September 11, 2001. The election was overshadowed by the September 11 attacks, which occurred shortly after polls opened.[1]
Stephen Lynch defeated State Senators Cheryl Jacques, Brian A. Joyce, and Marc R. Pacheco, former federal prosecutor William F. Sinnott, housing advocate John E. Taylor, and activist William A. Ferguson Jr. for the Democratic nomination.
State Senator Jo Ann Sprague defeated State Republican Committeeman William D. McKinney for the Republican nomination.
Stephen F. Lynch won the general election. He defeated his nearest competitor, Jo Ann Sprague, by over 22,000 votes.