TOPEKA, Kan. — Vanquished Republican Senate candidate Milton Wolf is expected to endorse Kansas Gov. Sam Brownback before the midterm elections, GOP sources said Wednesday.

Brownback, a Republican, faces an unexpectedly tough re-election bid in usually deep red Kansas, and the GOP has worked hard to unite the party in the aftermath of a bitter Senate primary. Wolf, a radiologist who affiliates with the Tea Party, lost a competitive race in August to incumbent Sen. Pat Roberts. Republican sources remain doubtful that Wolf will publicly back Roberts, citing hurt feelings left over from a vicious primary.