Lucy Flores is the first Hispanic woman ever elected to serve in Nevada's state legislature. And so she seems, on paper, like a likely Hillary Clinton supporter — women overwhelmingly support Clinton, Hispanics overwhelmingly support Clinton, and elected Democrats overwhelmingly support Clinton.

But Flores doesn't support Clinton. And her explanation of why is one of the most powerful, telling documents of the 2016 campaign. She begins with a child she met when she was researching early childhood development. I apologize for the lengthy quote, but it's worth it:

The child was about 5 years old – a young black boy who even despite his living conditions had a smile on his face and a twinkle in his eye. I made my way through my standard questions – "How often do you read?" "Sometimes, when I’m in school." "How often does your mom read with you?" "Never." "Do you enjoy reading?" "Yes." "How much? On a scale of sad face to happy face, point to the face that shows how much you enjoy reading." He pointed to happy face. So on and so forth. When we got to the end, I told him he did great and began to put away my things. As I was packing, he abruptly pointed to something and said, "Can I have that?" I didn’t have anything special so I looked at him confused and asked, "Have what?" "That." He said, still pointing. I looked down again and saw that my happy face assessment sheet was at the top of my stack of papers. I immediately realized he wanted to keep my sheet - my black and white, photo-copied a thousand times over, sheet that had sad to happy faces on it. Then I realized how anxious he seemed that I might say no, so I asked, "Do you have any books at all in there?" "No." "Do you have anything to read at all? A magazine or something?" "No." "Do you have toys? Or anything to play with?" "No." "Do you have anything at all? Like crayons or pens or something?" "No." And then it struck me: this bright kid, this happy, starry-eyed kid, this kid with all the potential in the world, had nothing. He had a filthy, dirty apartment with no active parenting, no role models around, and I was about to make his week just by giving him my happy face sheet. So I said, "Well of course you can have my sheet!" Then I started to furiously dig around my bag to see what else I could find. I found some neon highlighters he could color with, a few extra happy face sheets, and some red and blue pens. I gave it all to him. Then I said, "Ok, I have to go now. Have fun coloring your sheets. And remember to read at school every chance you get!" He happily nodded as he walked back into his filthy apartment. I walked to the sidewalk, sat on the curb, and sobbed uncontrollably. I sobbed with despair I hadn’t felt, well, ever. I knew as soon as I walked away what was likely in store for that kid – I knew the odds were against him, just like they were against me. I knew that statistically-speaking, he was likelier to end up in prison or dead than end up attending college.

It's worth pausing here to say a word about Clinton. If there is a single throughline to the bulk of her career, it's her unceasing advocacy on behalf of children. One of her earliest jobs in Washington was as a lawyer for the Children's Defense Fund. Her book It Takes a Village was all about what society owes to children. In the late 1990s, she was a driving force behind the creation of the Children's Health Insurance Program, which brought down the rate of uninsured children from 14 percent to 7 percent. And her commitment persists in this campaign: Her boldest proposals are probably her plans for guaranteed paid parental leave and universal pre-K.

All of which is to say that a deep concern for the living conditions of children is probably the best reason to support Clinton. But that concern isn't leading Flores to support Clinton. It's leading her to support Bernie Sanders. And the reason it's leading her to support Sanders speaks to Clinton's biggest political problems.

One of these problems is the one Matt Yglesias pointed out. He was struck by these sentences from Flores's piece, which come right at the end:

I believe that Bernie Sanders will lead the charge, with many millions of Americans behind him, against the unfettered Wall Street greed that has threatened the very existence of the middle class and shackled so many more to permanent poverty. I believe that now, more than ever, America needs a political revolution.

As Yglesias observes, they show that Sanders is "tapping into the exact same emotional current that Obama did" — the desire for a fundamental remaking of American politics. Clinton's promise is, effectively, that she is the best suited to grinding out incremental victories within a broken, gridlocked system. She might be right about that, but it's not nearly as inspirational as Sanders's promise — implausible as it may be — to lead a political revolution that fixes the system entirely.

But I was struck more by the sentences that come right before Flores's endorsement of Sanders's political revolution. She writes:

I believe that Bernie Sanders wakes up every day with these things on his mind. That the unfairness of it all weighs on his heart, just like it does mine, and that when he is elected, he will do whatever it takes to make America the land of opportunity again.

This, I think, is the core of the problem Clinton faces. There is no commitment dearer to her than her longstanding, unceasing work on behalf of children. Her roots in that effort run much deeper than Sanders's — as engaged as he is by the class war, there's no evidence that he's as personally or politically passionate about children as Clinton is.

But Sanders has nevertheless convinced Flores that he cares about the child she met, that he is angry about the injustices that child faces, in a way Clinton simply hasn't.

In 2012, much was made of the fact that Barack Obama polled behind Mitt Romney on all sorts of measures but had a huge, persistent lead when voters were asked whether the candidate "cares about people like me." Sanders's fundamental advantage over Clinton is that as voters get to know him better, they come to believe he cares about people like them in a way Clinton doesn't. Whether that's true or not is, politically, beside the point — it's a huge and growing problem for Clinton that Democrats like Flores think it's true.