Cellucci was challenged in the Republican primary by Treasurer and Receiver-GeneralJoe Malone. The race between Cellucci and Malone was acrimonious, with each candidate accusing the other of committing ethical violations. 
On September 16, Cellucci defeated Malone to win his party's nomination. 
Former Congressman and Kennedy family member Joseph Patrick Kennedy II was considered to be the early front-runner for the Democratic nomination, but personal and family problems resulted in him ending his campaign in August 1997. 
Cellucci's Secretary of Consumer Affairs Jane M. Swift, defeated Malone's running mate, radio host Janet E. Jeghelian for the Republican nomination.  Cellucci chose Swift as his running mate after Secretary of Administration and Finance of Massachusetts Charlie Baker and Suffolk County District Attorney Ralph C. Martin II declined to run.
In a January opinion poll, Cellucci lead Harshbarger 50%-30%. By August, Harshbarger had taken a 37%-35% lead over Cellucci.  After Harshbarger's primary victory, many moderate Democrats who had voted for McGovern or Donnelly, chose to support the socially liberal, fiscally moderate Cellucci instead of the more liberal Harshbarger. 
On November 3, Cellucci defeated Harshbarger by 65,317 votes.