At the debate last week in South Bend, Gregg said he took "great offense" at Pence's plans to promote traditional families, which Gregg said would ignore single parents such as himself. Pence said he understands what it's like to be raised by a single parent and cited his wife's experience growing up.
Pence has argued his "roadmap" for the state would best build upon Gov. Mitch Daniels' tenure.
The debates are sponsored by the Indiana Debate Commission.