Third-party candidates having outsize impact on election

Alexandra Jaffe
Gary Johnson (l) and Jill Stein (r).
Getty Images

The protest vote could cost Hillary Clinton the election.

Third-party candidates are taking small but solid portions of the vote in a handful of key swing states, keeping some too close to call by collectively outnumbering the votes giving Republican Donald Trump a thin lead.

It's an improbable and outsize impact for Libertarian Party nominee Gary Johnson and Green Party nominee Jill Stein, neither of whom cracked double digits in public polling or made it into the general election debates — and a sign of just how dissatisfied Americans remain with their options for president.

More from NBC News:
Meet Kamala Harris, the second black woman elected to the US Senate
House Speaker Paul Ryan wins reelection
Florida Trump supporter 'Pulled a gun Out' during argument Over candidates

In Michigan — a must-win for Clinton, as the map has narrowed for her over the night—Johnson and Stein were collectively taking a little more than 75,000 votes around 11 p.m. ET, more than double the nearly 37,000 vote lead Trump enjoyed in the state, and 5 percent of the vote.

In Florida, a must-win for Trump, Johnson, Stein and two other third-party candidates on the ballot collectively drew over 290,000 votes, again more than twice as much as the 135,000-vote margin that's kept the race too close to call throughout the night, and 3 percent of the vote.

Florida Republicans are feeling optimistic about Trump's chances there, and a Florida win would be a major boost on the path to 270 electoral votes for the GOP nominee. And in New Hampshire, Johnson alone was taking over 17,000 votes — more than the 15,700 vote lead Trump posted around 11 p.m. Collectively, third-party candidates were taking more than 22,000 votes there, nearly 5.5 percent of the vote.

That same story is playing out even in swing states where Clinton has the advantage. NBC News called Virginia for Clinton, and around 11 p.m. ET she was winning the state by nearly 57,000 votes. But Johnson, Stein and independent Evan McMullin collectively won more than three times that sum, taking 5 percent of the vote overall.

The strong performance by third-party candidates this year echoes that of independent candidate Ross Perot in the 1992 election, when he drew nearly 19 percent of the vote and helped deliver Democrat Bill Clinton a landslide win over incumbent Republican President George H. W. Bush.