Don Bolduc | New Hampshire Public Radio

Don Bolduc

James Gathany / CDC

A group of New Hampshire doctors wants two Republican U.S. Senate candidates to walk back recent statements opposing mandatory vaccinations.

Josh Rogers | NHPR

Retired Brigadier General Don Bolduc is running for U.S. Senate.

Bolduc is the first Republican to challenge incumbent Democrat Jeanne Shaheen in her bid for a third term.