Here's why young voters are abandoning Clinton and Trump

Young voters cheer for presidential candidate
Andrew Harrer | Bloomberg | Getty Images

If Hillary Clinton or Donald Trump is relying on younger voters to carry them over the finish line in this election, they'd better look elsewhere.

The stark truth is starting to appear in several polls: The latest New York Times/CBS News poll showed that a whopping 36 percent of voters under 30 planned to vote for a third-party candidate such as Gary Johnson or Jill Stein.

However, the implications are very different for Trump and Clinton. For Trump, the lack of support from young people simply signals a missed opportunity. For Clinton, not getting their support or seeing a significant portion of it migrate to Johnson or Stein in crucial states like Michigan and Pennsylvania could be a death blow.

Right now, Johnson and Stein are collectively polling above the 10 percent level among all voters in the Real Clear Politics average of all polls. That may not be enough for either of them to be included in the debates, but it's an historically stunning level at this stage in the election cycle. Consider that Ralph Nader had less than 3 percent of the vote in just one state in 2000, and that was enough to tip the election to George W. Bush. Imagine what a double-digit collective third-party percentage could do in this contest. Third-party candidates have only crossed the double-digit threshold twice in the last 50 years.

You can't really blame Clinton or Trump for this. Traditionally, voters aged 18-25 have been the weakest group as far as turnout. The Democrats got spoiled by the super surge in younger voters who turned out in 2008 to vote for Barack Obama. In some states, it appears those younger voters made a key difference. Their turnout dropped off a bit in 2012, but it was still historically higher than usual. Now, a large number of younger voters aren't making it through the pollsters' "likely voter" screens.

Younger voters are much more likely to be idealistic and back candidates that conventional wisdom tells them cannot win. The enormous support for Bernie Sanders earlier this year stood out as a prime example of that. Clinton did try to gain their interest with her proposal for debt-free college tuition much earlier this summer. But for some reason, her campaign flat out stopped talking about that proposal almost as quickly as it rolled it out. Trump has tried to make the case that his trade policies will help younger workers, but that never really got off the ground among millennials who seemed much more likely to view those policies as nativist.

And then there's one more thing: Remember just how old these leading candidates are. Trump is 70 and Clinton turns 69 in October — and that's REALLY OLD as far as 18-25 year olds are concerned. I know, it didn't hurt the 74-year-old Sanders with younger voters but here's the difference: He campaigned on issues that were uniquely focused on things important to young voters. Trump and Clinton can't make that kind of an issues pivot with about 50 days to go before Election Day.

Here's another reason why this is more devastating for Clinton. On the flip side, older voters tend to have strong, unflappable turnout at the polls. According to the Census Bureau's take on the 2012 election, voters in their 50s and 60s beat 18-25 year olds and even voters in the 40s by at least 20 percentage points in most comparisons.

And guess who older voters are most likely to vote for in this election? Trump. He has double-digit leads among voters over 45, according to recent polls.

Commentary by Jake Novak, senior columnist. Follow him on Twitter @jakejakeny.

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