Hillary Clinton got her long-awaited endorsement from Bernie Sanders today, in an event designed to unify the Democratic Party base heading into their national convention. Although there are still plenty of "Bernie or Bust" die-hards out there, Democrats had already largely unified behind Clinton, even before Sanders officially endorsed her today. Perhaps this all would have played out differently in a different election year, but Donald Trump is proving to be a powerful unifying force among Democrats -- because his elevation to president is seen as being downright unthinkable by both Bernie and Hillary supporters. Getting behind Hillary may be problematic for some Bernie supporters, but considering the alternative is a big motivating factor for most.

Polling has consistently shown that Democrats have come together much faster and to a greater extent than in 2008, when over 20 percent of Hillary supporters said they'd vote for John McCain rather than Barack Obama. This percentage only dropped down to 14 percent by the time people actually voted. Polling done since the end of the primaries this year shows only eight or nine percent of Sanders supporters saying they'd vote for Donald Trump. A higher percentage of Democrats overall is now fully on board with Clinton than happened in 2008 as well. So the party is indeed unifying around their candidate.

The biggest concern Hillary Clinton now faces is whether she can generate anywhere near the enthusiasm that Bernie Sanders created among his supporters. Voting in a negative fashion (voting against someone rather than whole-heartedly for someone) is seen more as a chore than as something to get excited about. Of course, there are many Clinton supporters who are indeed very enthusiastic about electing the first woman president (and for many other reasons), to be fair. But Clinton is going to need Sanders campaigning for her to have a shot at getting his core demographics excited about voting for her in any way.

A new poll out from the Associated Press and the University of Chicago shows how much ground Clinton has to make up among young voters. Among voters 30 and under, Clinton does beat Trump, but the numbers aren't very impressive. Clinton gets 38 percent to Trump's 17. That's a comfortable margin, but when you consider that Barack Obama won this demographic 60-37 (in 2012) and 66-32 (in 2008), Clinton obviously still has some work to do.

The numbers that should worry Clinton's campaign, though, are all the people who didn't respond with either "Trump" or "Clinton." A whopping 45 percent of young voters responded that they were undecided, wouldn't vote, or would vote for a third-party candidate. More young voters (22 percent) say they're voting for someone else than say they'll vote for Trump, in fact. Such high numbers plainly show the lack of enthusiasm for Clinton among young voters.

Minds can change the closer we get to Election Day, though. The anti-Trump sentiment is going to grow between now and then, it can safely be assumed. Of the 38 percent of young voters who responded they'd be voting for Clinton, 47 percent say they "mainly support Clinton" while 53 percent say they "mainly oppose Trump."

This may be a bit sobering for those enthusiastically supporting Clinton, but when you get right down to it, a vote is a vote. The measurement of who voted for what reason is not germane to who wins, in other words. An unenthusiastic anti-Trump vote for Clinton counts just as much as an excited-about-Hillary voter's ballot.

Most voters have, at one point in their lives or another, faced such a dilemma. Voting for a disappointing candidate whom you didn't originally support (because the other party's guy is so unacceptable) is actually a fairly routine part of American politics. Nobody gets the perfect candidate to vote for every time, to state the obvious. So most voters have lived through the experience already.

Except for those young enough never to have faced such political disillusionment, of course. In other words, Bernie voters. Assuming that Barack Obama was acceptable enough, this means anyone who has come of age from 2005 onwards may be facing the scenario of voting unenthusiastically for the first time. And that covers just about everyone from age 30 on down to those turning 18 before this year's Election Day.

The youth vote is notorious for not actually showing up to vote. Young voters did actually turn out in hordes for both of Obama's elections, which was a surprise to many pollsters who figured that they'd vote at their historic (meaning "low") rates. This year may signal a return to the norm if young voters stay away from the polls in droves in November. The danger for the Clinton campaign isn't that they'll be voting for Trump, but instead in overestimating how many of them will actually turn out to cast their ballot. If Team Clinton assumes her numbers will equal Obama's, they may be in for a shock. To be fair, though, I personally doubt that the Clinton campaign will overestimate their support among young voters in such a fashion. I think they're smarter than that.

Bernie Sanders himself will play a big role in convincing his supporters to vote for Hillary Clinton. The smartest thing for the Clinton campaign to do now would be to send Bernie out to states where he beat her (such as Michigan) or came close (Ohio and Illinois, perhaps). Bernie has now won enough concessions from Clinton -- both in the issues she campaigns on and in the official party platform -- to honestly throw his support behind her. He has made her a much more progressive candidate, and they have now officially buried all the hatchets from the hard-fought primary season. He needs to get out there and make that case to his base of support, in an effort to convince them to vote for Hillary Clinton. Seeing Bernie on a stage today with Hillary may have been massively disappointing for some of his most fervent supporters, but for most Democrats it comes with a big sigh of relief. The party is now (mostly) unified, heading into their national convention. This bodes well for Hillary's chances in November.

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant