The special election to choose a successor to former state Senator Linda Dorcena Forry of Dorchester will be held May 1.

The Senate adopted a special election order on Monday, and Secretary of State William Galvin, who oversees elections, released an election calendar featuring an April 3 primary and a Feb. 20 deadline for nomination signatures.

Candidates need at least 300 certified nomination signatures to quality for the ballot. The First Suffolk Senate district stretches from Mattapan north to the Seaport and includes South Boston and Dorchester.

Dorcena Forry resigned Friday, midway through her two-year term, to take a job with Suffolk Construction Company.