The key to a Trump win could come down to one thing

Voters wait in line for casting their ballots during early voting for the 2016 general election at Forsyth County Government Center October 28, 2016 in Winston-Salem, North Carolina.
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Voters wait in line for casting their ballots during early voting for the 2016 general election at Forsyth County Government Center October 28, 2016 in Winston-Salem, North Carolina.

Donald Trump is gaining in the polls after the FBI revealed a new batch of emails possibly related to the Hillary Clinton email scandal. Trump even took the lead Tuesday in the same ABC News tracking poll that had put him behind Clinton by 12 points just a week earlier.

What's happening here? Are Clinton supporters turning on their candidate because of the email scandal?

Not exactly. Most Clinton supporters had their minds made up long ago and the email scandal probably didn't change many minds. Where Trump is gaining is among independent voters.

If that trend holds, Trump could win the White House.


"Another question is whether Trump can make this lead among independents stick. Remember that his appeal to independents has almost nothing to do with him. As long as he avoids any major missteps and this email probe remains prominent in the news, independents are likely to continue moving in his direction simply by default."

First, let's look closer at those independent voter numbers. The latest Rasmussen Reports poll has the overall race tied, but gives Trump a 13-point lead among independents. In the ABC tracking poll, Trump has jumped out to a 19-point lead. The Investor's Business Daily tracking poll has Trump leading among independents by 15 points. And while the NBC/Survey Monkey poll that gives Clinton a 6-point overall lead does not have any specific presidential choice data from independents, it does say that more independents believe the news of the re-opened FBI probe into Clinton's email is very important by a 37-point margin.

Why are independent voters responding so strongly to the email scandal? The answer can be found by examining why so many voters identify or register as independents in the first place. These are the people who find so much to dislike in the established Democratic and Republican parties that they just can't join either one. Scandals are especially explosive for these kinds of voters. But not all of those scandals are created equal. Independent voters who distrust the powers that be in government are logically much more likely to react negatively to a corruption probe about say ... use of a private email server to skirt the law, as opposed to say ... an 11-year old tape of a candidate saying some really vulgar stuff about women. It doesn't matter if anything legally comes of the renewed focus on Clinton's email scandal, it's the fact that it's back on the front pages and mobile home screen that turns so many independents off. That's what that NBC/Survey Monkey data tells us loud and clear.

And, in recent years, the number of Americans identifying as independents has been growing steadily. That growth has been fueled by younger voters who have a hard time digesting longer running partisan battles. A 2014 Pew Research Center study showed that 39 percent of America voters identify themselves as independents, up from barely more than 30 percent in 2008. Early voter data from the crucial state of North Carolina shows just how strong this unaffiliated voter surge is. Compared to 2012, the number of voters registering in that state as Democrats is down 3 percent, the number of registered Republicans is up about 9 percent, and the number of unaffiliated registered voters is up a whopping 39.5 percent.

How important is the independent vote? It was always crucial even before this election. Consider the fact that more Republicans voted in the 2012 elections than Democrats, but President Barack Obama beat Mitt Romney because the number of independent or officially unaffiliated voters supporting him was big enough to erase that party line deficit. And in this election, it's important to check which battleground states where the independent vote is going to potentially make the most difference. In addition to the surge of independents in North Carolina, note that swing states like Colorado and New Hampshire have percentages of registered independent voters greater than the national average. And Florida does not have as many of independent voters by a basis of overall state percentage, but it does have about 3 million registered independents who could easily swing an election. Pennsylvania, with well over 1 million independent voters, is in a similar boat.

Another question is whether Trump can make this lead among independents stick. Remember that his appeal to independents has almost nothing to do with him. As long as he avoids any major missteps and this email probe remains prominent in the news, independents are likely to continue moving in his direction simply by default.

This rise in registered independents seems to tell us the country is getting less polarized. And that feels like good news all around. Of course that also makes calling this election tougher, as the usual suspect voters and voting blocks simply aren't as large as they once were. But independents have always decided presidential elections in the past and they will this time again. And that's very good news for Trump and his supporters in this final week before Election Day.

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

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