In 2016, Gary Johnson ran for the presidency on the Libertarian Party Ticket. He averaged 2.95% of the vote in four states.
If those votes went to Hillary Clinton, Clinton would have won Florida, Pennsylvania, Michigan, and Wisconsin.
Few recall the presidential candidacy of Gary Johnson. But Johnson, running as a libertarian, won nearly 5 million votes nation-wide.
What might have been the result in our last election had Johnson not been on the ballots in several close races?
If Clinton could have won the votes cast for Johnson she would have won :
> Florida's 29 Electoral Votes
> Pennsylvania's 20 Electoral Votes
> Michigan's 16 Electoral Votes
> Wisconsin's 10 Electoral Votes
Had Clinton received Johnson's votes her Electoral College total would have been 307 to Trump's 306.
Could third party candidates determine the outcome in 2020?
I doubt it. If anything Johnson took votes away from Trump. Now Jill Stein might have taken some from Hillary. History shows the Libertarians are Republican leaning while the Green Party leans towards the Democrats. If there wasn't any third party candidates in the states you mentioned, Trump's margin would have been larger, not smaller. Hillary lost those states and the general election because independents, the non-affiliated swing voters didn't like her. They disliked her more than they disliked Trump. On election day among independents and independents only, Trump was viewed favorable by 40% of them, unfavorable by 57%. Hillary, independents viewed her 27% favorable, 70% unfavorable. Questions 10 and 11.
https://d25d2506sfb94s.cloudfront.net/cumulus_uploads/document/l37rosbwjp/econTabReport_lv.pdf
History shows folks usually don't vote for someone they dislike. But what if they disliked both major party candidates? They vote third party or stay home, in fact 12% of all independents did exactly that, voted third party against both candidates.
https://www.cnn.com/election/2016/results/exit-polls
Trump won the White House because he won the independent vote nationwide, 46-42 over Hillary with 12% voting third party. 9 million people voted against both Trump and Clinton.
In Pennsylvania independents went to Trump 48-41 with 7% voting for Johnson and 3% for Stein.
In Wisconsin independents voted for Trump 50-40 over Hillary with 6% voting for Johnson and 2% for Stein.
In Michigan independents voted for Trump 52-36 over Hillary with 7% voting for Johnson and 3% for Stein.
In Florida independents voted for Trump 47-43 over Hillary with 5% voting for Johnson and 2% for Stein.
Hillary's problem was she ceded the campaign trail to Trump. From 1 Sep 2016 through 8 Nov 2016 Trump made 116 campaign visits, stops, rallies to Hillary's 71. That 71 looks larger than what it was as it includes fund raisers in deep blue California and New York. Look at the deciding states, Wisconsin, five visits, stops, rallies for Trump to none for Hillary. In Michigan it was Trump six, Hillary one. Pennsylvania was closer, 8 for trump 5 for Hillary. even in electoral vote rich Florida, Hillary ceded the campaign trail there to Trump also, 13 visits, stops, rallies for trump, 8 for Clinton.
Fact is if Johnson supporters had to vote in a two candidate race, most would have went to Trump, Hillary would have gained most of Jill Stein's. Advantage Trump.
I wouldn't blame Johnson, I'd blame Hillary for ceding the campaign trail. Perhaps even Sanders supporters. The Democratic base or those who identify with the Democratic Party voted for Hillary 89-8 over Trump with 3% voting third party. Sanders supporters did vote for Hillary, but by a 75-12 margin over Trump with a whopping 13% voting third party. Who knows how many of Sanders supporters stayed home?
Bernie Sanders Voters Helped Trump Win and Here's Proof
Then there was CNN's exit polling which asked the question of third party voters who would they have voted for only in a two candidate race, no third party candidates. 19% answered Trump, 16% Clinton, the rest said they wouldn't have voted.
One other thing, in Feb 2016 a poll showed that 56% of all Americans wanted the Democratic Party to nominate someone other than Hillary Clinton. The Democratic Party faithful didn't listen to all of America which was their right, no doubt about that. It's Democrats who decide their candidate, not America as a whole. But all of America decide the general election, not just Democrats.
I'm one of those who voted for Johnson. My disgust for both major party candidates made me go to the polls and vote against both Trump and Clinton as I wanted my vote against both of them officially registered. If I had been forced to choose between Trump and Clinton with no other option, I'd have stayed home or wrote in a vote for Mr. None of the Above. Even knowing what I know today, I'd still vote against both Trump and Clinton.