So two things:
1. The thing which need to be most realized in this speech is how he is saying we can do this.
I know Obama said "Yes, we can" as well but that was marketing as he took campaign donations from big banks. Sanders is not using a SuperPAC. He is only taking small donations from the public. As such, if people actually want him to win they have to step up and promote the hell out of Bernie. He's not gonna get much media exposure (he doesn't have sufficient funding for campaign ads on TV.) He's not gonna be seen nearly as much on Facebook as compared to other candidates who pump money into sponsored posts. He will often likely get snubbed by MSM who prefer the other candidates who are Status-quo.
2. The other version of the word we he uses (the more important version.)
The biggest thing to gather from Sanders' candidacy is the need to organize on a grassroots level. Make connections, meet people, organize for how to improve the political and socio-economic circumstances of this country. I honestly do not think Sanders will win unless he is really really clever with his outreach. He is not going to be sensational. He going to touch on major issues. The media, and the pubic, are suckers for sensational (the actual issues are boring to most people.) Even if he loses the election that should not be the issue because NO ONE should be looking for a savior president. Yes, Sanders is Jewish but he's not the second coming of Jesus so get off your need for a messiah and realize that congress matters too, and public organizing matters too. Sanders will be just as ineffective at getting legislation passed as Obama has without a congress that works with him.
If you want him in office you'll need to haul it with person-to-person outreach (I know, God forbid we don't do all our outreach on the computer where we are at the mercy of algorithms,) and social media promotion (I know that's slightly contradictory.)
If he doesn't win office, remember what you learned while organizing for him to win... and continue.