The candidates vied to replace Eric Massa, who resigned the seat on March 8, 2010, as a result of health issues and allegations of sexual harassment.

Republican Thomas W. Reed Jr., the former mayor of Corning, New York, defeated Democrat Matthew Zeller and write-in candidate Janice Volk.

[3] On March 3, 2010, following allegations of sexual harassment and reports that he had suffered a recurrence of cancer, Massa announced that he would retire at the end of his term.

[4] On April 23, 2010, Steuben County Republican chairman Bill Hatch announced that he would file a lawsuit that, if successful, would force Governor David Paterson to acknowledge the vacancy and call a special election in the immediate future.

[9] Judge David Larimer issued a ruling in the case on June 4, 2010, officially acknowledging the vacancy but declining to compel Paterson to call a special election before November 2.

[11] The Democratic Party chose Matthew Zeller, a 28-year-old CIA analyst who had not lived in New York since he had left for war, as their candidate.

Zeller was an ROTC-trained Army officer who served in Afghanistan and holds master's degrees in international relations and public administration.