Sally Kohn is an activist, columnist and television commentator. Follow her on Twitter: @sallykohn . The opinions expressed in this commentary are hers.

(CNN) If Donald Trump weren't dominating the coverage in this election, Bernie Sanders would be the big story.

While Trump is a self-funded billionaire who was well-known before he ran and benefited from a highly fractured Republican field in which no one could coalesce enough votes to challenge him, Bernie Sanders is a relatively unknown senator who used small donations to mount a serious and sustained challenge to Hillary Clinton's campaign, one of the best-oiled political juggernauts of the past half century.

If the right word to describe Donald Trump supporters is angry, the best word to describe Bernie Sanders' supporters at this point might be surprised.

The New York Times' Yamiche Alcindor wrote , "Covering Mr. Sanders is at times like watching a man almost surprised by his success and eager to make it last." In my experience, his supporters feel the same -- a sort of "Can you believe this is happening?" mix of elation and shock.

These are the voters who were perennially accustomed to holding their noses and voting for the least-worst option and then spending the rest of their time railing against the corrupt center-right system. I should know, I'm one of them.

They/we/I never expected to see a presidential candidate championing universal single payer health care -- let alone, gasp, that candidate have a shot at winning. I suspect that candidate didn't see it coming, either.

But unlike Trump, who is, I think, encouraging and even goading his supporters' deep hostility toward government and elected leadership, part of the revolution Sanders talks about is a newfound belief that the system really could change if we try to change it. Whatever the outcome of the election, Trump supporters will crawl under rocks or join up with militant militias or just grow older and die.

But Sanders supporters mark a new, enthusiastic bloc of citizens who because they have faith in a candidate like Sanders now have renewed faith in the system in which he is thriving.

As a result, these supporters may increasingly see government as a potential tool for change -- one that can work well if we work to change it. Whether he wins or not, I expect the biggest part of Sanders' legacy will be a generation of engaged, honest and bold leaders who work within government and not just outside and against it.

And in that sense, Bernie Sanders isn't going away. Neither is his message. Or his voters.

Not in this primary. Not in the general election. And not in the foreseeable future of American politics.

And just as the Republican Party will now have to grapple with the angry, alienated voters fracturing off from the GOP establishment, the Democratic Party will have to address the seemingly far larger number of hopeful, idealistic and energetic voters who have bolstered Sanders campaign. Polls show Sanders beating Trump in a potential general election match-up by an average of 17 points.

While the Republican Party figures out how it can possibly be even more anti-immigrant and anti-woman, the Democratic establishment has to reconcile its hawkish, centrist, big business and Wall Street cozy policies of the past several decades with the strong populist pull of the Democratic base.

And Democrats are going to have to contend with these voters not just because they're shaking their fists every couple of years but because they're running for office and taking over local party infrastructure and energetically filling and reviving positions in government bureaucracy.

To the extent that Donald Trump may be killing the Republican Party, Bernie Sanders is doing the opposite -- reviving the Democratic Party and imbuing it with a new generation of engaged, optimistic leadership. Bernie Sanders has already changed the current election with his dogged focus on income inequality and economic justice. Sanders' supporters will change elections and politics for decades to come.

That is not to say the Democratic primary is over yet. Sanders is still holding on and showed last weekend that he can keep racking up wins. He brings momentum into next week's Wisconsin primary.

And his campaign is, I think rightly, pushing superdelegates to retract their anti-democratic support for Hillary Clinton and instead side with the voters in their states. But whatever happens, when November comes and goes, Sanders' campaign won't be over.