Editor’s note: Today’s Midday Poster was authored by The Daily Poster’s new editorial fellow, Aditi Ramaswami. This editorial expansion is due to our subscribers' support — thanks again for being part of our team!

Sen. Kyrsten Sinema, the conservative Democrat from Arizona, has emerged as a chief roadblock to Democrats’ plan to allow Medicare to use its bulk purchasing power to negotiate significantly lower prescription drug prices. Her opposition, which comes on the heels of a pro-Sinema ad blitz funded by drugmakers, could derail a plan that could save the government billions and cut the cost of many drugs by more than half.

As it turns out, not too long ago, Sinema promised Arizona voters something very different about drug prices.

Find out what that was and much more in today’s Midday Poster below, exclusively for subscribers.