Most state and federal primary elections in the U.S. are divided up by political party, and many are only open to voters who are members of a party.

Reform-minded advocates and many political scientists say this system is not working. They say relatively small numbers of voters are selecting their nominee — often in a district or state that leans strongly toward one party, so whoever wins the primary cruises to victory in a general election.

The group Unite America underscores what it terms the "primary problem" with this finding: In 2020, "only 10% of eligible Americans nationwide cast ballots in primary elections that effectively decided the winners in a supermajority (83%) of Congressional seats."

Experts and advocates say this electoral process excludes voters and leads to more extreme candidates who mainly appeal to activists, and could be exacerbating partisan polarization.

That's why there is a movement to rethink how states set up their primary elections and how voters choose which candidates advance to a general election.

From smoke-filled rooms to party primary elections

Modern-day party primaries in the U.S. originated about 100 years ago, according to Kevin Kosar, senior fellow at a right-leaning think tank called the American Enterprise Institute. He says the earlier system "was often riddled with corruption," and party primaries were created to allow voters a say in who got on their ballots.

"Back in those days, voters and various good government groups got fed up with candidates for office," Kosar says. "Those who appeared on the ballot were being selected by party bosses in smoke-filled back rooms. So the idea was, let's take this party selection process and open it up to the public."

Jeremy Gruber, senior vice president for the advocacy group Open Primaries, says at first, political parties were not happy with this change.

"Parties decided to make peace with primary elections," he says. "And rather than fight them, they began to claim [primaries] were theirs, not the voters'."

That's why at the beginning most primary elections were "closed," meaning you had to be registered with a party to participate. Gruber says initially these primaries worked well because almost everybody was either a Democrat or Republican.

Closed vs. open primary systems

But in the past few decades more voters have identified as independent.

"What's happened is the electorate has gone through a massive sea change over the last 25 years," Gruber says. "Now, independents are the largest and fastest-growing group of voters in the country. Over 50% of our young people — the next generation of voters, millennials and Gen Z voters — are independent."

This is at least partly why many states have moved away from closed primaries. Only 16 states — including populous Florida and New York — still have either completely or partially closed primaries.

"So if you're an independent voter in those 16 states ... you do not get the right to participate in the primary," Gruber says. "Your taxes pay for them, but you don't get the right to participate. You only can participate in the general elections."

Lawmakers in Pennsylvania and New Mexico, for example, have considered legislation that would open their closed primaries to independent voters by letting them pick a party primary ballot to fill out.

There are efforts in some states to close primaries, however. In Colorado, the Republican Party sued the state in an effort to close its primary elections so that unaffiliated voters — Colorado's largest voting bloc — can't vote in them. In their suit, Republicans say political parties have the right "to choose their nominees for office without interference by those who are not members of the party."

Supporters of closed primaries have argued that sabotage from non-members is a serious issue and that voters who want to vote can simply register with the party that's most closely aligned with their views. According to the Pew Research Center, the vast majority of independent voters tend to "lean" toward either the Republican or Democratic Party.

The polarization problem in U.S. primaries

Gruber says states with closed primaries also have more polarization.

"You are starting to see states that shut out independent voters have primary elections that are more and more insular and are producing candidates that are less and less representative because fewer and fewer people are able to participate in them," he says. "And that's throwing the whole system of democracy in elections out of whack."

AEI's Kosar says polarization isn't unique to closed primary states, though. Voters have self-sorted themselves and are polarized on their own, but he puts some blame on partisan primaries.

"After 100 years of experimentation with this, we see that there are clear problems with this system — not least of which is that it produces candidates who frequently aren't particularly representative of the average voter," Kosar says. "And that is an issue for democracy."

Gruber says this is why nonpartisan primary elections are ideal. He says candidates who run in a nonpartisan system "no longer have sort of the necessary fealty to their party's agenda," compared with candidates who have to run in a party primary.

"They can run based upon entirely how they see their constituency and the issues that their constituency prioritizes," Gruber says. "You're starting to see a lot more representative politicians coming out of all of these systems ... so, we believe that a move to nonpartisan primaries as a public function is in the best interests of every state."

5 states with nonpartisan primary elections

There are currently five states that run federal or statewide nonpartisan primaries: California, Nebraska, Washington, Alaska and Louisiana.

In these systems, all candidates from all parties are listed on the same ballot, and voters can vote for any candidate. In California, Washington and Nebraska's statehouse elections, the top two vote-getters — regardless of party — move on to the general election. In Alaska, the top four vote-getters move on. These systems are often referred to as "top-two" and "top-four" primaries.

Louisiana has perhaps the most unique system. In October during odd-numbered years and in November during even-numbered years, all the candidates appear on the same ballot. If a candidate wins in a majority (50% plus one vote) in their race, they win that election outright. If no candidate wins a majority, the top two vote-getters — regardless of party — run in a second election the following month. In that second election, whoever gets the most votes wins.

Kosar says states considering moving to a nonpartisan system will have to choose what works best for their population.

"Different voting systems are going to work differently depending on the demographics," he says. "A voting system that produces the best results for a purple state may not work so well in a deep red state."

For example, he says, a top-two system would work well in a purple state because you are likely to get two candidates from different parties.

"But if it's a deeply blue or deeply red state, you're going to have a very narrow difference between the two candidates being put forth," Kosar says. "And that may not be the best."

More states are considering nonpartisan primaries. There are tentative proposals in South Dakota and Idaho, for instance. And Nevada voters will weigh final approval of a nonpartisan "top-five" system next year.

What research says about nonpartisan primaries

Gruber, the open primary advocate, says existing nonpartisan systems have already led to some significant changes. In California and Washington, which have had top-two primaries for over a decade, he says he's seen "quite a few things that I think are very positive," including more bipartisanship.

But as far as whether these systems have led to the election of more moderate candidates, research has been mixed. A 2017 study published by Cambridge University found "an inconsistent effect since the reform was adopted" in both California and Washington.

"The evidence for post-reform moderation is stronger in California than in Washington, but some of this stronger effect appears to stem from a contemporaneous policy change—district lines drawn by an independent redistricting commission—while still more might have emerged from a change in term limits that was also adopted at the same time," the researchers wrote.

A newer study, from 2020 from the University of Southern California, however, did find evidence that the top-two system in that state "reduced ideological extremity among legislators, relative to those elected in closed primary systems." Researchers wrote that the "ideological moderation in top-two and open primaries" was found among both incumbents and newly elected legislators.

Andrew Sinclair, an assistant professor at Claremont McKenna College in California, says the effect of nonpartisan primaries on voter engagement and satisfaction is somewhat mixed so far.

In deep red or deep blue states, general elections are not competitive and tend to disengage some voters. But if candidates are chosen in a top-two system, there could be a pretty competitive race between two candidates in the same party.

For example, a top-two primary could have a moderating effect in a race between two Democrats in a deeply Democratic state. That's because presumably Republican and independent voters would weigh in on the race too.

"The argument for moderation is that possibly the more moderate Democrat would have an advantage in that election," Sinclair says, "or perhaps the more competent or the more pragmatic [candidate]."

But Sinclair says concretely identifying that this system "actually has produced a moderating effect is hard" for a whole bunch of reasons.

"There are some political science papers that argue that there is one," he says. "Some argue that there isn't, but that it produces these types of elections in those places is pretty indisputable."

And elections with top-two candidates of the same party can have a serious downside, Sinclair says.

"The downside of the top two is that in those kinds of elections some Republicans don't vote," he says. "Some Republicans will say, 'Well, there's no, you know, person of my own party on the ballot, so I'm just going to skip this race.' And that's true. There is some roll-off in participation."

But Sinclair says this roll-off is what creates moderation.

"What it effectively has done is move the Democratic primary into the general election in those places," he says. "And that dramatically increases the number of Democrats and independents participating, and not all of the Republicans roll off ... and even if some Republicans roll off, you get some Republicans voting. And that's the pathway for moderation."

Regardless of the various tradeoffs, Kosar says, ideally states would be more experimental with how they structure elections so that politics become more palatable to voters — which he thinks is a laudable goal.

"A number of these electoral reforms aim to either depolarize or at least disincentivize gratuitous, bad or toxic behavior, which in many cases is rewarded by the current system," he says. "Being a jerk, being obnoxious, savaging others is rewarded. So if you change the incentives, the politicians are going to run differently. And I think a lot of people like that."

• 
•