1978 New York's 21st congressional district special election
Member Herman Badillo, who had served for 8 years, was appointed deputy mayor of New York City. He resigned December 31, 1977 from the U.S. House to become Mayor.
On February 14, 1978, Democratic state senator Robert Garcia easily beat fellow Democrat Louis Nine in a special election. Garcia had to run on the Republican election line, but was accepted back as a Democrat, once elected. He would continue to represent the district for 12 years.
| District | Incumbent | Party | First elected | Result | Candidates |
| Herman Badillo | Democratic | 1970 | Incumbent resigned December 31, 1977 to become deputy mayor of New York City. New member elected February 14, 1978. Democratic hold. | √ Robert Garcia 55.40% Louis Nine 24.46% Ramon S. Velez 15.87% Armando Montano 2.74% Israel Ruiz Jr. 1.52% |