lapdog (n.) Look up lapdog at Dictionary.com
also lap-dog, 1640s, from lap (n.) + dog (n.); figurative sense of "subservient person" is by 1950.
Senator McCarthy (R-Wis) renewed his Communists-in-Government charges today and called Senator Tydings (D-Md) the Truman administration's "whimpering lap dog." [AP news story, Aug. 7, 1950]