Who cares about these polls with both under 45%...we all know MO will go for Trump by a solid margin in the end.
If Gary Johnson gets 10% of the vote in Missouri, then he will allow Hillary Clinton or Donald Trump to win the state with about 45% of the vote. Democrats have a floor of about 45% in Missouri, and that could be enough to win this time.
I look at the three-way race as the reality this year.
Only in your mind.
The math needs not stay in my mind. If Gary Johnson gets 10% of the vote, then the winner needs only 45%. Should Hillary Clinton campaign actively in Missouri, perhaps to support the Democratic challenger for a Senate seat (Barack Obama stayed away from Missouri in 2012, figuring that he could only hurt the Senate campaign of Claire McCaskill), and still got about 45% of the popular vote in Missouri.
What is 'new' about my math? Take away 10% from 100%, and someone who gets 45% wins.
So let's look at how previous non-winning Democrats did in Missouri:
Obama 2012 44.28 (good for staying away from the state!)
Obama 2008 49.23 (razor-thin loss)
Kerry 2004 46.10
Gore 2000 47.08
Dukakis 1988 47.85
Mondale 1984 39.88
Carter 1980 44.35
McGovern 1972 37.71
Even if Jimmy Carter could have won Missouri had John Anderson gotten a little over 11% of the vote in Missouri. McGovern and Mondale had problems other than Missouri, of course.
...Hillary Clinton can win without Missouri. Should she win it the state is likely the difference between about 360 and 370 electoral votes. But she must campaign in Missouri, which will require the Democratic nominee for the Senate to seek her support.
We are all free to interpret the dynamic reality of this Presidential campaign. I know what I want -- Hillary Clinton winning the Presidency and having a Democratic wave that wins the Senate and the House 'back' for her. Such is my bias. I admit it.
I see the potential for a Trump collapse -- but it hasn't happened yet, so I don't count it. You may expect the Johnson/Weld campaign to collapse, but so far I doubt that it will. This is arguably the best third-party campaign, with two nominees who have good reason to take more Republican support away from Donald Trump than from Hillary Clinton. Both Johnson and Weld have experience in elective office. Not counting racist secessionists George Wallace and Strom Thurmond whose support was basically regional, this is the strongest third-party ticket since Theodore Roosevelt and Hiram Johnson. I'm not saying that Johnson/Weld will fare better than Ross Perot...
You may believe that Hillary Clinton is a horrible nominee, worse even than Obama -- but that is your opinion.