doughface
n.
contemptuous nickname in U.S. politics for Northern Democrats who worked in the interest of the South before the Civil War; it was taken to mean "man who allows himself to be moulded." The source is an 1820 speech by John Randolph of Roanoke, in the wake of the Missouri Compromise.
Randolph, mocking the northerners intimidated by the South, referred to a children's game in which the players daubed their faces with dough and then looked in a mirror and scared themselves. [Daniel Walker Howe, "What Hath God Wrought," 2007]
Mask of dough is recorded from 1809, and the same image Randolph used is attested in another context by 1833. In contemporary use the expression was explained as referring to "the pale doughy faces of his frightened opponents" [Craigie] or "to liken them in timidity to female deer," which is frightened at her own shadow.