There is unbelievable uncertainty in today's primaries. Here is what to watch for:

- Utter chaos in Ohio
- Do voters show up?
- Does Biden's coalition hold?
- What signs does Sanders send?
- Future elections in question

w/ @ericbradner & @jeffzeleny: https://t.co/DF9MCVYG7S

— Dan Merica (@merica) March 17, 2020