LITTLE ROCK, Ark. — Betty Bumpers, whose advocacy of childhood immunization won her national recognition while serving as first lady of Arkansas and after accompanying her husband, Dale L. Bumpers, to Washington when he won a Senate seat, died on Friday in Little Rock. She was 93.

Her son Brent said the cause was complications of dementia. She had been in failing health and had recently fractured a hip, he said.

A native of tiny Grand Prairie, Ark., Mrs. Bumpers had been content with her life as an elementary schoolteacher and homemaker in nearby Charleston, where her husband was born, when he rocketed to the Arkansas governorship in 1970, running as a liberal Democrat and a relative unknown.

Once installed in the governor’s mansion, Mrs. Bumpers was startled to discover that tens of thousands of Arkansas children had not been inoculated against common but potentially fatal diseases like measles, mumps and diphtheria.