Affiliations with Al Gore and Democratic Party
In the 1980s, the Phelps family were strong political allies with then-senator Al Gore. The home of Fred Jr., Phelps' eldest son, located in the Westboro compound, acted as Gore's campaign quarters for one of his senate races, and the Westboro compound was host to a fundraiser. Numerous photos exist on the internet of Fred Phelps Jr. and his second wife, Betty Phelps-Schurle, posing with Al and Tipper Gore in Phelps Jr.'s home. Phelps also served as a Gore delegate on the floor of the Democratic National Convention in Atlanta in 1988. (link with photos.)
http://www.lcrga.com/archive/200010251159.shtml
During the 1992 presidential election, Fred Phelps and Fred Phelps Jr. led the members of Westboro in campaigning around the state of Kansas for Bill Clinton and Al Gore; Fred Phelps Sr. would later state in fliers that he did so with the belief that Gore would fall under WBC's political influence should he and Clinton win the election.
In January of 1993, Fred Phelps, his wife Marge, Fred Phelps Jr., and Betty Phelps-Schurle were invited to (and attended) the innagural ball in Washington D.C.
Well, browsing through the link you provided says it all. Just reading what's under the heading, "Notable Activities and statements" was quite enough.