By Sarah John, FairVote USA, info@fairvote.org

After six months of voting and caucusing, the world’s most participatory process for nominating party candidates is coming to an end. Culminating this month in national conventions where the Republican and Democratic presidential nominees will be formally chosen, this fiercely contested nomination process took in primary elections in 38 states (and DC) with caucuses in more than a dozen states. The competitiveness of the elections helped ensure that voter turnout remained at historic 2008 highs, with around 60 million Americans (more than one in three of the eligible electorate in those 38 states) participating in the process to choose the two major-party presidential nominees.

In the Democratic Party, turnout was lower than it was during the battle between Barack Obama and Hillary Clinton in 2008. In 2016, fewer citizens cast ballots in the Democratic primaries than in the Republican primaries. Yet, still, one in six adult citizens voted in Democratic primaries in the 37 states that held them. In Texas, voter turnout fell the most, down by more than half (from 19% of the state’s eligible population in 2008 to 8% in 2016). In 35 other states, turnout in the Democratic primary also declined. Only in Michigan, in Bernie Sanders’ surprise victory over Clinton, did turnout increase in the Democratic Party presidential primary from 2008—rising to 16% of the state’s eligible population. It should be remembered, however, that in 2008 the Michigan primary was shrouded in controversy, as the Democratic Party determined that the date of the primary was in violation of party rules and (initially) stripped the state of its convention delegates.

New records were set in the Republican Party, with voter turnout increasing by half on 2008.  Voter turnout was up significantly in almost every one of the 38 Republican primaries – reflecting the competitive and “energetic” nature of the race.  In 2008, only around one in ten (10%) eligible Americans voted in the Republican primaries; in 2016, one in six (18%) did. In two states, Wisconsin and Rhode Island, Republican turnout more than doubled.

That turnout is up so much in Republican primaries in every state states indicates that the contest between Donald Trump and his losing adversaries brought in Republicans who sat out the 2008 contest between John McCain, Mike Huckabee and Mitt Romney.  But more than just returning Republicans, the evidence hints at large numbers of independents and some Democrats driving the high Republican turnout.

Some states hold “closed” primaries, in which voters must affiliate with a particular political party when they enrol in order to vote in that party’s primary.  Other states hold “open” primaries, in which an enrolled voter chooses, irrespective of their party affiliation, which party’s primary they will cast a ballot in at the polling place. In states that held open primaries for both major parties in both 2008 and 2016, turnout in the Republican primary increased by an average of three-quarters, more than double that of closed primary states. This suggests that unaffiliated voters, who were unable to vote in closed primary states, made up a significant part of the Republican open primary electorate this year.

Additionally, in the open primary states, plenty of Democrats likely chose to participate in the Republican presidential primary. The New York Times’ Upshot blog reported that Southern conservatives registered as Democrats are some of Trump’s “very best voters”, and there were likely a good deal of registered Democrats who switched parties in open primary states. Even in closed primary states, where people had to change their voter enrolment in advance of the election to indicate their new party affiliation, there is evidence that more voters than usual have switched from the Democratic Party to the Republican Party. There were efforts to encourage enrolled Democrats to “ditch and switch” to the Republican Party to vote for Trump. The numbers of switchers in closed primary states is likely relatively small. In Pennsylvania, for example, only an estimated 200,000 voters switched parties in the lead up to the primaries, and less that 130,000 of those to the Republican Party, representing about 1% of the 8. 3 million enrolled voters in that state. In open primary states, where there is no need for switchers to change their enrolment, and so we would expect the percentage of switchers to be larger.

While it is unusual to think of the 2016 Republican presidential nomination process as anything but chaotic, reflecting a party in disarray or cannibalizing itself, the energy this nomination season ensured that more people than ever were involved in choosing presidential party nominees. It remains to be seen whether the Republican Party coalesces around Trump, but it is important to recognize that many people who had been inactive or had dropped out of democratic participation have been brought into the process this election season.

Thanks to Molly Rockett and Demarquin Johnson for the research on which this post is based.