Hillary Clinton's support among millennials is lukewarm and millions are ready to abandon the Democratic nominee for a third-party candidate in November.

A nationwide Quinnipiac poll released on Wednesday found that Clinton's support among young voters is a strong 55 percent in a head-to-head matchup against Donald Trump, just five points lower than Obama's number in 2012.

But, when millennials were given the choice to vote for Libertarian Gary Johnson or the Green Party's Jill Stein, a stunning 43 percent of young Clinton supporters abandoned her in favor of a third-party candidate.

In a four-way race Clinton earns just 31 percent of the millennial vote, less than half of what Obama received in 2008. Johnson emerges in second place among young voters, gaining 29 percent, and Trump follows him within the margin of error with 26 percent. Jill Stein is in a distant but healthy fourth place with 15 percent of the youth vote.

Without a large base of millennials to support her, Clinton's national lead drops from four percent to just two percent -- well within the margin of error.

A study by the Center for Research and Information on Civic Learning and Engagement at Tufts University found that 60%+ support was crucial to Obama's 2012 victory, and was responsible for his wins in Ohio, Pennsylvania, Florida, and Virginia.

Clinton won't be able to count on the same level of support as long as millennials choose principles over party politics.