Was this guy:

That’s J. Joseph Garrahy, who became Governor after serving eight years as Lieutenant Governor. Of course, back then, that meant he had been President of the Rhode Island Senate for eight years, with two different governors serving over him (Licht and Noel). Garrahy became governor over Cranston Mayor James Taft, the Republican (likely of the Taft family, who beyond having a legacy in Rhode Island also have ties to the Chafees and the Lippitts). At the time, governors served two-year terms as well.
I remain unconvinced that the office of Lieutenant Governor serves too much importance in the modern Rhode Island, and I think that while it is an office that is largely what its office-holder makes of it, it also requires much leeway from the Governor. Witness the far more productive second term of Elizabeth Roberts under Lincoln Chafee’s tenure than under Donald Carcieri.
So I think it’s very unlikely the next Lieutenant Governor has much of a shot at becoming Governor.
UPDATE: Where have our governors come from? Since Garrahy, our governors have been:
- Mayor of Cranston
- President & CEO of a department store/WJAR (they were one company)
- U.S. Attorney for Rhode Island
- CEO of a ceramics and glass company
- a former U.S. Senator