I presume he is using it the same way most of us do, as a reference to the subset of fundamentalist Christians who bring discredit upon their faith by being obnoxious blowhards and/or demanding government support for their preferences.
It's like the difference between "Trekkie" (an annoying little munchkin in ill-fitting Spock ears) and "Trekker" (a normal Star Trek fan).
The idea of Christian Fundamentalism first emerged as a movement in the 19th century within various Protestant bodies, who reacted against the rising tide of evolutionary theories and modernist Biblical criticism. From a Bible conference of Conservative Protestants meeting in Niagara in 1895, a statement was issued containing what came to be known as the five points of fundamentalism: The verbal inerrancy of Scripture, the divinity of Jesus Christ, the virgin birth, a substitutionary theory of the atonement, and the physical resurrection and bodily return of Christ.¹ In the first half of the 20th century, most Protestant churches in the U.S. were divided into either Fundamentalist or Modernist groups. The term has generally been applied to all those who adhere to strict, conservative (Protestant) orthodoxy in the matter of Biblical inspiration.
http://www.victorious.org/chur21.htm