"These methods, which have been around for so long, may be losing some of their accuracy because circumstances have changed," Scott Keeter, a senior survey adviser at Pew Research, told the Atlantic. "Whether there has been a change in our politics in just the last two years that makes all of this less accurate is really impossible to answer at this point."
And those likely voter models -- the ones that are used to show Jill Stein's low support -- are generally weighted to expect fewer young and first-time voters. That happens to make up a large share of the Green Party's base, so a model that fails to take these voters into account will have Jill Stein underperforming.
There are other good signs for Jill Stein that may have not yet shown up in the polls. For one, October is traditionally a time when the polls tighten and third party voters begin to "come home" to the two major party candidates. That is one of the main reasons why third parties have underperformed polls in most recent election cycles. Back in 2012, Jill Stein polled between 1 and 2 percent in polling through the summer but ended up with a little more than 400,000 votes nationwide.
In a post-mortem analysis, Salon noted that the tightening race led many people away from the Green Party. Although Barack Obama ended up beating Mitt Romney comfortably in the electoral map, national polling leading up to Election Day suggested that the two were within about a point of each other.
As Salon noted, Stein fared poorly because the perception of a close race scared many people away from voting third party.
"Why'd she fail? Pretty obvious. Media coverage of the race suggested that it would be close. Stein, like Nader, collapsed when protest voters got skittish about throwing the election away from Obama. You can see this best in Florida, where Stein currently has 8,757 votes. In 2008, Nader got 28,128 votes in Florida. (He ran on the Ecology Party ticket.)"
The 2016 general election appears to be moving in the opposite direction. After Donald Trump's terrible performance at the first debate, his campaign has been in freefall and his poll number sinking.
With Hillary Clinton appearing to be headed toward a comfortable victory over Donald Trump, the argument that "a vote for a third party candidate is as good as a vote for Donald Trump" has lost all steam, and third-party voters will likely be sticking with their first choices.