The Democratic electorate is shrinking, as I explained in this blog post, by the secession of moderates and conservatives from the party’s nomination process. So what is happening to the Republican electorate? It’s expanding, primarily but not entirely by the addition of more evangelicals.
Here are the numbers, extrapolated from exit polls, showing in rounded-off thousands the total vote in the Iowa caucuses and New Hampshire and South Carolina primaries, the turnout of evangelicals (estimated for New Hampshire in 2008) and of non-evangelicals.
| State/year | Total | Evangelicals | Non-Evangelicals |
| Iowa 2016 | 187 | 120 | 67 |
| Iowa 2012 | 122 | 70 | 52 |
| Iowa 2008 | 119 |
71 |
48 |
| New Hampshire 2016 | 284 |
71 |
213 |
| New Hampshire 2012 | 248 |
55 |
193 |
| New Hampshire 2008 | 240 |
53 |
187 |
| South Carolina 2016 | 738 |
531 |
207 |
| South Carolina 2012 | 604 |
393 |
211 |
| South Carolina 2008 | 446 | 245 | 201 |
We see two patterns here, one in the two Northern states and one in South Carolina. In Iowa and New Hampshire, turnout of both evangelicals and non-evangelicals was almost identical in 2008 and 2012. In 2016, turnout of both groups increased, by a larger percentage among evangelicals than non-evangelicals. In South Carolina, in contrast, turnout of non-evangelicals has remained almost exactly the same in all three years. But evangelical turnout increased sharply — by almost 150,000 voters — in both 2012 and 2016.
Ted Cruz has argued that he would be a strong general election candidate because he would increase evangelical turnout over what it was in November 2008 and 2012. Such an increase has in fact occurred in the first three Republican contests, but Cruz has not necessarily been the beneficiary. He carried evangelicals in Iowa, which helped him beat Donald Trump overall. But Trump edged him out among evangelicals in New Hampshire and South Carolina, and in the latter Marco Rubio came in a close third among that group.
Why are so many evangelicals voting for a candidate like Trump who, at least over the long haul, has not embodied their own beliefs? And despite the fact that in the past they have tended to give the lion’s share of their support to candidates who appear to embody them? The best explanation I’ve seen is provided by Ben Domenech in The Daily Beast.
In the past, he argues, evangelicals sought a candidate who was clearly on their side in the culture war. Now, having lost the culture war, many are prepared to back a candidate who speaks out sharply against the demands for political correctness by the culture war victor. So even though Cruz and, in a more muted way, Rubio have signaled they have consistently shared cultural/religious conservatives’ beliefs, many evangelicals are willing to vote for Trump, even though he hasn’t, because he has shown he will speak out for them.
Whether Trump as nominee would spur evangelical general election turnout as much as Cruz or Rubio would is an open question.
