What's most remarkable about the national CNN-ORC poll released on Monday is how little things have changed since early October. Donald Trump continues to lead with whites who didn't graduate from college; he even stretched his lead a bit. Hillary Clinton continues to lead with nonwhite voters; she extended that lead a little. Back then, Clinton led by 5 points in a four-way contest. Now? She leads by 5 points.

But that doesn't quite tell the whole story. One big change is that Gary Johnson, the Libertarian candidate, saw his support drop by half. He can console himself with the fact that the change was within the margin of error, but that change is both explained within the poll -- and also predictable.

Polling that includes Johnson has shown him drifting lower in support over the past month or so.

This comports with what often happens to third-party candidates as the election nears. Polling in the mid- to late summer often over-represents how much support third-party candidates will get. Once it comes time to actually vote, a lot of that support moves back to the major-party candidates.

In the case of Johnson, the drift appears to have been a function of men walking away from his candidacy. Clinton and Trump each gained 2 percentage points between the two CNN-ORC polls. Johnson lost 4 percent. Johnson lost 7 percentage points from men, but none from women. Those men split between Clinton and Trump roughly evenly.

This is one poll, so we can't say for certain that support that Johnson is eroding is being split between the two candidates. But the erosion in Johnson's support is real. His peak in the RealClearPolitics polling average came right after the appearance on MSNBC when he asked, "What is Aleppo?" on Sep. 8. That day he was at 9 percent in the polling average. Now, he's at 5.9.

That slide has overlapped with Clinton's increased national lead. The two are correlated -- but not necessarily linked causally. Trump saw a dip in support, too, which helped Clinton pull away from him. But the net result is that Clinton's lead over Trump is now about equal to Johnson's support overall.

Meaning that even if Trump got all of Johnson's support, which is unlikely, he would only barely close the gap with Clinton.

It seems safe to assume that the Libertarian Party will, for some time, regard this election cycle as a missed opportunity. Two deeply unpopular major-party candidates. An electorate so thirsty for an alternative that a guy who sort of randomly decided to run for president named Evan McMullin seems poised to potentially win the state of Utah. But a Libertarian candidate who blew repeated chances to offer an alternative.

It's also looking increasingly safe to assume that the Republican Party will regard this election as a missed opportunity, too. Trump went through two debates and a month of campaigning as Election Day approached and didn't make a dent against his Democratic opponent. If nothing changed over the last three weeks, weeks that included debates, what's likely to change over the next two?