Dear Bernie Sanders,
42% of Americans identify as Independent, and 65% of Americans would support a third party candidate. On the Republican end, 25% say they will consider a third party candidate if Trump wins the nomination. As I'm sure you've seen during your campaign, Americans are clamoring for another voice in the race.
You've said repeatedly that you will do everything you can to make sure a Republican doesn't make it into the White House. It turns out there is a mathematical possibility of an Independent winning the race. And by running Democrat, you have already secured the 15% requirement in national polls that would allow you to join the presidential debates along side Trump and Clinton.
You yourself have seen the polls that show Trump beating Hillary nationally. It's estimated that a fourth to a third (sometimes even higher margins) of your supporters refuse to vote for Hillary in a general election. Outside of your supporters, it's scary to realize Clinton's favorable ratings continue to drop and that she's never been able to raise her poll numbers in any campaign she's run.
I still have hope that you can overtake Hillary's delegate lead and present a challenging case to the superdelegates in July. But if that doesn't happen, if Hillary is the Democratic nominee, I ask you not to put yourself behind such a weak candidate who could so easily lose the general election. Your campaign has always had the momentum. I ask you to keep it going.
If, for whatever reason, you can't or won't continue, I ask instead that you endorse Jill Stein. Many of your supporters are already interested in her campaign. Many are also prepared to vote for her in lieu of writing in your name on the November ballot. Your endorsement could raise in her the polls, giving her the 15% she needs to join the debates. Not only, would she provide a fresh voice against Trump and Clinton, but she'd represent a woman candidate for President worth voting for.
I will continue to fight for your win, but if it doesn't happen, please don't back the establishment we've all been fighting against. That would be the biggest momentum killer of all.