Conservative regions where George H.W. Bush's support in the 1992 presidential election exceeded his national vote average all had above-average increases in same-sex couples since 1990. Conversely, regions where Bill Clinton's support was above his national vote average all had increases of same-sex couples below the national average.Lots more at the link.
The Williams Institute study also found that state recognition of same-sex couples was inversely related to increases in the number of same-sex couples reporting their relationship. From 2000 to 2006, states that created formal recognition of same-sex couples had below-average increases, while states that prohibited marriage between two people of the same sex experienced above-average increases in same-sex couples.