"Demoncrat” ("demon" + “Democrat,” with capitalization optional) is a derogatory nickname for a member of the Democrat party. “Demoncrat” is cited in print from at least 1992 and has been popularly used on websites and blogs from about 1999.

Similar Democrat nicknames include “Demoncrap” (since 2000) and “Demonrat” (since 2000).


Wiktionary: Demoncrat
Etymology
Blend of demon and democrat
Proper noun
Demoncrat (plural Demoncrats)
(US, slang, pejorative) A member of the Democratic Party (with a demonic implication).

Urban Dictionary
Demoncrat
A liberal Democrat as perceived by a Bible-belt conservative Republican. An amalgamation of the words “demon” and “democrat.”
Only a true demoncrat could be in favor of unrestricted abortions.
by Accu May 29, 2006

21 August 1992, Buffalo (NY) News, Convention Notebook:
One sign that drew attention on the convention floor was “Exorcise the Demoncrats,” held by a traveling evangelist, the Rev. Robert Schenck of the Town of ...

15 July 1995, Wichita (KS) Eagle, pg. 2D:
Huie, who ran for the Legislature in 1994, talked of being called a “demoncrat” and said Broadfoot’s opponents called her an “evil witch.”

23 November 1997, Los Angeles (CA) Times, Life & Style, pg. E3:
Marilyn also likes to call the Democrats “the Demoncrats” for obvious reasons.

Google Groups: misc.survivalism
Newsgroups: misc.survivalism
From: (Gunner)
Date: 1999/12/29
Subject: OT- Demoncrats

Google Groups: alt.politics.clinton
Newsgroups: alt.politics.clinton
From: “Mike”
Date: 2000/07/22
Subject: Bush, the alleged Texas deficit, and the DEMONcRAT spin machine

Google Groups: alt.politics.clinton
Newsgroups: alt.politics.clinton
From: “Mike”
Date: 2000/02/10
Subject: DEMONcRATS trying to influence the Rep primary

16 August 2008, Washington (DC) Times:
Demon-crat values