The Collaborative International Dictionary of English v.0.48:
Heeler \Heel"er\, n.
1. A cock that strikes well with his heels or spurs.
2. A dependent and subservient hanger-on of a political
patron. [Political Cant, U. S.]
The army of hungry heelers who do their bidding.
Moby Thesaurus II by Grady Ward, 1.0:
33 Moby Thesaurus words for "heeler":
Conservative, Democrat, Labourite, Republican, Tory, Whig,
adherent, appendage, dangler, dependent, follower, hanger-on,
hatchet man, henchman, loyalist, man, partisan, party faithful,
party hack, party man, party member, party wheelhorse,
registered Democrat, registered Republican, regular, retainer,
satellite, servant, shadow, stalwart, tagtail, ward heeler,