It's hard to find a definitive source stating where the party falls in the political spectrum because it's an opinion, not a fact.  All you can find are opinions.  But there are a lot of those.  Here are a bunch of sources supporting the far-right position:    And, to be fair, there are also some sources supporting the "right-wing" position.  But sources for the "center-right" position are very hard to find unless you turn to really weird places like the IDU.  Try googling Republican and "center-right."  You'll find some articles on how the party once was "center-right," but precious little saying that it is right now.  I'm sure somewhere in the bowels of the internet, there is a source supporting "center-right," but I haven't been able to find one.