Mostly venting, but yes a prediction involved. However, let me address a couple of your points. On the Hillary being unpopular: that is not up for debate. She is. Her net favorability rating is something like -25. Trumps is the only one worse at around -40. The only one with a positive is Sanders at something like +10. And people have been voting for the "socialist". Independents and progressive Democrats have been. In contests where anyone can vote, Bernie has been winning by a lot. In contests where only (D)s can vote, he's been losing...by not a lot. Almost all of Clinton's lead has been through early voting. Sanders almost beat her election day in NC, and DID beat her on election day in AZ, MO, and IL. So even though she "has more votes"* it's much more complicated than that. So...in the elections where a larger portion of the demographics of the country can vote, he's been winning, and in the ones where there's a biased portion of the electorate voting he's been losing.
And the country is right leaning....kind of. Until you look at actual preferences of policies. Most progressive policies are well received by a majority of Americans, and most conservative ones aren't. We have one of the worst turnouts in the developed world. And Sanders has been getting first time voters out where he can (re: open state primaries). In states where turnout is large, he wins. I repeat for effect: in states where turnout is large, he wins. This is decidedly not just young people. It's also people who haven't voted because they've had no candidate. So yes. There is a rather significant portion of progressives out there that is untapped.
As for the labels? Obama is left of center. Hillary is at best dead center. And that's for American spectrum of politics. She's way too hawkish to be considered a liberal. She's espoused support for a LOT of conservative view points over the years, so I am very skeptical of this new, more progressive Hillary**. Going simply by her campaign statements, over the past two months at least (but not the months before that! She's changed positions on a large number of topics as Sanders has been catching up!), she's fairly progressive, almost halfway to where Sanders is. I don't trust for an instant though that she's going to keep these views in the General, much less her presidency. And my point in the previous post was that this is a humongous problem. In an election defined by lack of trust in the establishment, pivoting to the center might well be a death knell. Also my point, is that do not make the mistake of assuming this anti-establishment uprising is confined to the clown car that was the RNC primaries, it exists in the left as well.
As many have noted, Obama has not been a true progressive. He's been fairly progressive, but he did walk back some of his more progressive agenda topics. Some for legitimate reasons (like the conservative and hostile House and Senate he's had to deal with) and some not so legitimate reasons (simply not doing it).
*She doesn't have more votes. It's impossible to tell. Even though she's beating him in voting primary votes, she's lost nearly every caucus (or every one? I forget which ones were caucuses). And caucus votes are not tallied directly. So we don't know how many people voted one way or another in the various caucus states, directly. We do know that they've tended to have record turnout, and Sanders has won those.
**Do I think Hillary will be a bad president? No. I do not. I think she is dangerous to elect, not because of what she will do to the country, but what lesson it will teach the DNC and the electorate about the process, and progressive ideals. I believe we are in a dangerous time, and at a turning point. We are not about to fall backwards, no, but we are in danger of doing some things that we as a country will regret later down the line. I do not think Hillary will be the cause of these things. I simply think her election might precipitate some of these things later on. This election's problem isn't the next four years. It's the fours years after that. And I believe that nominating Sanders would prevent the problems of those four years.
In summary, I really really really hope Hillary is now a progressive. Because if she's not, the DNC just lost a lot of elections. And that is bad for our country because the people that will be winning those elections are the Todd Youngs of the world. Who's Todd Young those of you outside of Indiana? He's Cruz, but worse. He's probably going to be the next Senator from Indiana. Sanders was the best thing to happen to the DNC in a long time, and they had better not waste it.
EDIT: On Clinton pivoting to the "center"? Well, there's already evidence that she's going to do it. Another reason I don't trust her not to do it. Up until the Michigan primary, the Flint crisis was her number 1 top priority. Then....nothing. Nothing more about it. Sanders keeps bringing up drinking water issues, but she hasn't. She also spoke at AIPAC. Also known as the conservative war hawk's wet dream convention. And got a standing ovation. After spouting peace talk. Then she's abandoned it. I don't know her stance on a number of things because it's changed so much so recently.