The problem that the Republicans have is very simple--only about 37% of registered voters can be counted on to vote Republican--If the Republicans want to win, they have to do some combination of the following:
A)Find a hot issue
B)Run a celebrity candidate
C)Promise a big tax cut
D)Get out the relatively small percentage of the population that still identifies with the "Stars and Bars" and all that it represents--

Many Republicans are strongly in favor of progressive social legislation, value a balanced budget, and value substance over style in their representatives,but the bottom line is that they want to win, so they do what it takes to win--Many Democrats(including some who run for office) have not caught onto this tactic yet, which is why we are in the situation we are in--