The sea change in 1994 was a "dribs and drabs" success for the Republicans, who were lucky enough to have Bill Clinton very publicly pushing noxious ideas, with the MSM enthusiastically pushing his agenda for him. Most people viscerally disliked the agenda. If you want the counter-example, look at the impeachment proceedings in 1998.
You didn't answer my question: what enabled the sea change that now has almost all major bodies of U.S. government controlled by Republicans?
Revulsion toward Bill Clinton? Really? You give him that much power?
OK, fine. What started the Bill Clinton impeachment? (Clue: www.drudgereport.com).
What was responsible for the defeat of John F'n Kerry? (Clue: www.swiftvets.com)
Other examples abound, you just aren't noticing it.