RALEIGH, N.C. — Spencer Stone of Cullowhee agrees with liberal viewpoints on almost everything. Jackson Lanier of Randleman leans mostly to the right.

But both freshmen at the University of North Carolina at Chapel Hill deliberately chose to register as unaffiliated voters, joining a rapidly growing and youthful segment of the state’s electorate that has officially rejected partisan labels. Both said their views don’t fit fully into either major party’s platform.

Unaffiliated voters reached a long-expected milestone this month in North Carolina when they became the second largest bloc of voters in the state, exceeding Republican registration for the first time.

“When you believe in what both parties are saying, you really can’t side with one,” Lanier said in an interview.

There were 2,056,294 unaffiliated voters last week, about 550 more than Republicans, with each group covering roughly 30 percent of the state’s 6.8 million registered voters, according to state election board data. Democrats still have the most voters with more than 2.6 million, but that number is basically flat since 2008 and their overall share has declined from 45 percent to 39 percent. Libertarian registrants have grown but remain a distant last.

Unaffiliateds — sometimes called independents — comprised less than 10 percent of the electorate in the mid-1990s. Their numbers have more than doubled since 2004. Eighty percent of the nearly 1 million new registered voters in the nine years ending in May registered as unaffiliated, an analysis by Democracy North Carolina says.

North Carolina political scientists, activists and strategists said in interviews there are political and societal reasons for the shift. Having no affiliation also can be attractive because these voters can choose to participate in either the Democratic or Republican primary — so candidates from the parties must keep learning how to win their support.

The bitter political atmosphere within the two-party system is a likely cause for the shift, said Michael Bitzer, a Catawba College politics professor studying registration trends. Forty percent of the registered voters known as millennials — those born since 1981 — are unaffiliated and the largest bloc among their age group, according to Bitzer’s research.

“Being children of political polarization, maybe this is a clear sign that they are not willing to associate with either party,” Bitzer said, noting these voters aren’t necessarily moderates: “Being unaffiliated does not mean you’re not partisan.”

Stone, who voted for Bernie Sanders for president in 2016, said his “generation is saying that we don’t want to be part of the warmongering, corporate Democrats and Republicans” and that the parties “need to change their platforms and appeal to a wider base.”

State Republican Party Executive Director Dallas Woodhouse and the conservative Civitas Institute don’t consider the drop to third place a problem for the GOP, saying net registration gains for Republicans have outpaced Democrats. Woodhouse said: “We’re going up and the Democrats are going down.”

Woodhouse said voting preferences for unaffiliateds align with percentages similar to the entire state. Still, Dee Stewart, a longtime Republican consultant, said the unaffiliated voting shift is a concern “in the sense that we’ve got to continue to modernize the way that we campaign.”

Stewart, who attributes the voter shift to people being less likely to join traditional civic, religious or neighborhood organizations, said unaffiliateds are more solution-oriented rather than rigidly ideological.

As for Democrats, state party Chair Wayne Goodwin blames what he calls power-hungry Republicans in the North Carolina legislature for frustrations about party politics.

“Democrats understand and hear this frustration and are reinvesting in people,” Goodwin said. He said Democrats are focusing on economic issues and year-round organizing so the public knows “exactly what we’re fighting for and how to get involved.”

Whether the increase in unaffiliated voters will translate into them having greater roles in state government remains unclear.

A bill still pending before the General Assembly this year would lower the number of signatures required for unaffiliated candidates to get on otherwise partisan general election ballots. But appointment methods to many boards and commissions usually encourage Democratic and Republican membership. A new law creating a combined state elections and ethics board — now being challenged in court — contains no spots for unaffiliated voters.

“The laws are very much stacked in favor of the parties,” said Bob Hall, executive director of Democracy North Carolina.