The union organizer Jane McAlevey talks about this thing called a "structure test". You might have a majority of workers tell you they'll support the union or go on strike, but as soon as the opposition heats up, a big chunk will flake and then you lose.
Instead of just relying on polling, you need to test your strength by seeing who will actually commit to smaller asks, like signing a public petition or marching into the boss's office as a group. Polling means much less than demonstrated willingness to take action.
This also applies to electoral politics. It's easy to tell a pollster you'll support Politician X, but that doesn't mean you'll actually go vote, or encourage your friends to, or volunteer for the campaign. The level of willingness to take action is an important factor that polls miss, particularly because general elections are not decided by mythical swing voters but by which side is better organized and turns out the most people. About half of the voting-eligible population participates in every election and are usually committed to one party, while the other half may not vote at all in any given election.decided by mythical moderate swing voters and choosing a primary candidate meant to appeal to them is only going to bring about a repeat of 2016.
That's why this map matters so much. Donating to candidates is the first structure test. One primary candidate has nearly double the number of individual contributors compared to the runner-up. He leads throughout most of the country, including nearly 100% of Ohio, Wisconsin, Florida, North Carolina, and Colorado. Many of these donors are people who are less reliable voters (Wal-Mart workers and the unemployed are the plurality) but his campaign has gotten them newly politically engaged. He also has a union-like organizing strategy where campaign volunteers engage with people who are reliable supporters but not necessarily reliable voters.
I am 100% convinced that Bernie is the most electable Democrat in the general election. Hillary lost due to a lack of enthusiasm in swing states -- her vote totals went down compared to Obama in 2012 while Trump's numbers were essentially the same as Romney's. This election won't be