Or they were simply mainstream Republicans. Traditionally the GOP was never a "conservative" party any more or less than the Democrats, it only captured more and more of the populist conservative base as the Democrats swung further to socialism and identitarianism. Traditionally (at least from a global perspective) both American parties were always kind of faux-centrist/liberal joints.

(though it is true that the Dems let themselves get infiltrated by international communism way back before most anyone here was born)