Nevada in 2020 had plenty of Trump/Yes voters on an amendment to repeal the state’s constitutional SSM ban, with Storey County, Douglas County, and Carson City being Trump/Yes jurisdictions. The amendment passed with 62% as Biden won just over 50%.
Do you have the link to results or a map? Or know of any other repeals voted on elsewhere? Not surprising that today gay marriage would outpoll Democrats in most states. But since most referenda on gay marriage were in the 00's, and gay marriage has become much more popular, and partisanship in voting has roughly stayed the same, it makes sense that there would be far more anti-gay anti-Trump than pro-gay pro-Trump.
One Maryland county (Frederick) that supported the state's same-sex marriage ballot initiative in 2012 voted for Trump in 2016, but it voted for Biden in 2020 comfortably. Androscoggin County, Maine, voted for that state's equivalent ballot initiative that same year but supported Trump both times.
Androscoggin voted against same-sex marriage in 2012 (I can't find the Maine 2009 results).
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Grand, UT, Nicollet, MN, Blue Earth, MN, and Winona, MN voted for Trump in 2016 but not 2020. As did Maricopa, AZ which voted against AZ's first referendum for the ban, but for its second referendum on the ban.
Can anyone check VA (it may be hard to figure out with those independent cities)?