Ah, the “Trump is bringing millions and millions of new voters into the Republicsn Party” meme. Consider this yet another myth, along with the one stating that Democratic primary turnout is predictive of general election turnout, that is being promoted by people with vested interests in its being believed:
A better way of looking at that claim is to consider how many new voters are turning out. This is hard to measure without full access to state voter files, but we can estimate.
For example, exit and entrance poll data reported by CNN tells us about how many of the people who’ve come out to vote in that party’s elections this year are first-time voters. Forty-four percent of voters in Iowa were doing so for the first time, compared with 16 percent in New Hampshire and 20 percent in Texas. The high was 62 percent in Nevada — one of the few states where Democrats turned out more heavily than Republicans. Adding it up, we get about 1.1 million people on the Democratic side who’ve come out to vote for the first time in a primary in 2016.
That’s not necessarily new voters. Democrats have a habit of voting only in the general election and skipping the primaries. But it’s an estimate.
We can also estimate how many of those people came out because of Bernie Sanders, the unexpected candidate who’s doing well with new voters on the Democratic side. In states where there were enough new voters for their vote preferences to be statistically significant, about 563,000 of those new voters backed Sanders. It’s safe to assume that he got about another 100,000 from the states where there were too few new voters to break out this measure separately. So, figure that Sanders spurred about 650,000 people go to the polls. That’s out of 6.2 million total voters. Impressive.
On the Republican side, the math is trickier. First and foremost, exit and entrance polls in most states didn’t ask Republicans whether it was their first time voting, only doing so in New Hampshire and Iowa. In those two states, about 127,000 people were voting for the first time, and about 42,000 of those were voting for Trump. That’s actually lower than the number of new voters in Iowa and New Hampshire that backed Sanders; he got about 68,000 votes from new voters in those two states.
That’s the second reason the math is tricky. Sanders has accrued 37.5 percent of all of the Democratic votes, to Trump’s 34.5 percent of the Republican one. (All vote result data is from the irreplaceable U.S. Election Atlas.) Sanders is trailing in the delegate count by a lot, and Trump is winning by a lot — but there are two Democrats and four Republicans. And there are four Republicans now; just over a month ago, there were still a dozen to split up the vote. In Iowa and New Hampshire, Trump got 30 and 38 percent of the new vote, respectively. Sanders got 59 percent and 78 percent.
So it seems safe to assume that, even with increased Republican turn-out, the number of new voters voting for Trump isn’t much higher than the number backing Sanders. It’s hard to believe that it has reached 1 million, much less “millions and millions.”