“Donald Trump must be defeated, and I will do everything in my power to make that happen … On Sunday night, in the first one-on-one debate of this campaign, the American people will have the opportunity to see which candidate is best positioned to accomplish that goal.” Bernie Sanders is staying in the Democratic race following a remarkable two-week run (including last night) when he went from the clear leader to a huge underdog.

+ Ron Brownstein in The Atlantic: “Tapping an enormous wave of grassroots energy in both bids for the White House, Sanders galvanized young people, transformed online fundraising, and changed the terms of debate in the Democratic Party on issues ranging from health care to college affordability. But as his defeats last night made clear yet again, his unflinching call for a ‘political revolution’ could not build a coalition broad enough to capture the ultimate prize.”