Please excuse my politics, and don’t take this as a tacit endorsement for any particular underling candidate, (I’m still undecided though I am starting to lean.)
“Can’t win” has always seemed circular to me. How does a candidate win? If people vote for them. Who do people vote for? Whoever they think has the best chance of winning. How does a candidate have a chance to win? If people vote for them. Around and around and around.
Insert media rhetoric about who “can” or “can’t” win, add to that a dash of “You wouldn’t want to waste your vote, would you?”, and you have a nice environment set up to have gatekeepers in the political process.
If the public were generally educated, had an idea of what their personal beliefs and convocations were (rather than just going along with their bias-confirming herd), were doing actual research on candidates (rather than bottle feeding from what media outlets are telling them), and matched candidates up against their worldview, the whole question of whether they “can win” or “can’t win” becomes irrelevant.