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(ANALYSIS) This seems like a lifetime ago, but the 2004 election was actually a really interesting one in terms of religion and politics. George W. Bush was seeking a second term, and his Democratic challenger was John Kerry.
The Republicans devised a strategy to goose turnout in a bunch of battleground states. Same-sex marriage was an incredibly salient issue at the time, and the majority of the public was opposed to allowing gay couples to get married. So, Republican parties in 13 states managed to get the question put on the ballot.
In all 13 states, the ballot measures that would enshrine marriage between a man and a woman passed with a majority.
That was even true in the state of Oregon, where 57% of voters said yes to this statement, โAmends Constitution: Only Marriage Between One Man and One Woman Is Valid or Legally Recognized as Marriage.โ
Did that strategy actually propel Bush to a victory in 2004? According to this paper from David Campbell and Quin Monson, it appears that White evangelical turnout increased in states with those amendments on the ballot.
But they also found that nonreligious voters turned out at much lower rates, and they argue this actually was more instrumental in Kerryโs loss.