Millennial voters — defined as those born since 1981 — are becoming a larger share of the electorate, and few are voting Republican. Yet polls suggest that while many millennials reject GOP nominee Donald Trump, many are also unwilling to vote for Democratic nominee Hillary Clinton.

Part of the problem is Clinton herself. Millennial voters, like other voters, feel she is inauthentic at best, untrustworthy at worst. The problem is not her age; millennials flocked to support Sen. Bernie Sanders (I-VT), who is older than Clinton and represents a naïve socialist philosophy that is a throwback to the 1930s. The problem is Clinton herself.

“Millennials hate Donald Trump and they dislike Hillary Clinton — just like the rest of America,” pollster David Winkler told the San Francisco Chronicle.

The problem also extends to the rest of Clinton’s party, which millennials distrust.

As Bakersfield.com reports: “Fewer than one out of every five Millennial voters in California is registered as a Republican. Not that the Republicans’ loss is the Democrats’ gain. Recent voter data shows that Millennials are the driving force behind the huge growth in Californians registering with no party affiliation at all.”

A study by NextGen Climate, the organization funded by billionaire climate climate change crusader Tom Steyer, found that Clinton has a problem among Sanders voters:

The study found that 1 in 5 of Sanders’ supporters wouldn’t vote for Clinton in a four-way race that includes Trump, Libertarian Party nominee Gary Johnson and Green Party standard-bearer Jill Stein. Of what the study calls “Sanders Holdouts,” 16 percent intend to vote for a third-party candidate, and 14 percent say they will sit out the election.

That problem may only become worse, not better, as reports of what happened at the Democratic National Convention filter out. Following revelations by Wikileaks that the Democratic National Committee had colluded with the Clinton campaign against Sanders, the party clamped down on Sanders supporters in Philadelphia in an effort to drown out their protests. Hundreds of Sanders delegates walked out of the convention in protest.

In California, millennials are expected to play a large role in deciding several of the ballot initiatives facing voters in November. Political consultant Gale Kaufman told Bakersfield.com: “Issues like guns, the death penalty and marijuana should evoke a lot of interest at the campus level and moving through Millennials. Social issues or values issues tend to energize younger voters.”

Democrats hope that Clinton will benefit from that turnout. But she still has much to do to earn the millennial vote.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. His new book, See No Evil: 19 Hard Truths the Left Can’t Handle, is available from Regnery through Amazon. Follow him on Twitter at @joelpollak.