Greg Sargent with the news:

The campaigns of Hillary Clinton and Bernie Sanders have agreed on a rough schedule for four new debates over the next few months, according to various sources, a move that shows the Democratic primary is now set to shift into a higher gear and signals we may be headed for a long, drawn-out battle. The four debates will be sanctioned by the Democratic National Committee, a spokesman for the DNC, Luis Miranda, confirms to me. “They will all be sanctioned,” Miranda says. The first of these will be tomorrow night on MSNBC. The second will be in Flint, Michigan (as Hillary Clinton has requested) in March; the third will be in Pennsylvania in April, and the fourth will be in California in May, a source close to the talks confirms.

Per the article, Sanders confirmed on CNN today. “To the best of my knowledge we have. We didn’t get all the commitments that I wanted. We got California, we got Michigan — and that’s good. I wanted a debate in New York City….but Secretary Clinton has not agreed to do that. But I believe we’re looking at a debate in Pennsylvania…but I do believe we have her commitment, as I understand it, for three additional debates.”

I’d be interested in seeing varying formats — a town hall debate, formats allowing longer-form give and take. One thing’s for sure: it would be difficult to have a Pennsylania presidential primary debate be as big of a trainwreck as the one we had here in 2008.