Raser moved to Reading from Alabama in 1851, opening two drug stores. At the time, painting was only his hobby but in 1871 he sold his stores to devote all of his time to painting. Initially he painted portraits, but he later painted marine scenes, still lifes, and landscapes, for which he is best known.
He was a member of the Art Exhibition Gallery and the Philadelphia Art Club and exhibited at the Pennsylvania Academy of Fine Arts from the 1870s through the 1890s. The artist painted in the Catskills at Haines Falls and Pine Hill Valley; along the Schuylkill River; and in the Connecticut River Valley and points farther east. He was a colleague of fellow Berks landscapist Dan Devlan and teacher of the painter Christopher Shearer.