CNN's announced debate over the new GOP health care bill has left congressional Democrats and reporters aghast at Sen. Bernie Sanders' (I., Vt.) presence on the stage.

The debate, pitting bill authors Sen. Linsey Graham (R., S.C.) and Sen. Bill Cassidy (R., La.), against Sen. Amy Klobuchar (D., Minn.) and Sanders, will take place Monday at 9:00 p.m., CNN announced.

Graham and Cassidy's bill is aimed at rolling back Obamacare ahead of the simple-majority reconciliation deadline on September 30. It focuses primarily on devolving responsibility for health care to the states. Sanders, meanwhile, has spearheaded efforts to introduce a "Medicare-for-all" healthcare system in a bill backed by 15 of his Senate colleagues.

Sanders' support for a single-payer system is part of why his presence in the debate is alarming Democrats. The Republican National Committee's talking points in support of the Graham-Cassidy bill make extensive reference to Sanders and his alternative proposal.

Center for American Progress Senior Fellow Topher Spiro, a leading voice on Twitter in support of Obamacare, thinks the debate will do harm to its chances of survival.

Thanks for nothing CNN. https://t.co/XAzuVOqU9R — Topher Spiro (@TopherSpiro) September 21, 2017

Tommy Vietor, an Obama speechwriter, also expressed frustration with the news of the CNN debate.

I'm not sure single payer vs Graham-Cassidy is the debate we want right now. https://t.co/toBHvusHug — Tommy Vietor (@TVietor08) September 21, 2017

Some journalists reported that Democrats expressed frustration over the debate.

A Democrat weighs in: "The only way Graham and Cassidy can pass their bill is a distraction. Bernie is serving one up on a silver platter." https://t.co/uYsAzyY1Y1 — Seung Min Kim (@seungminkim) September 21, 2017

(It took 30 seconds for a Dem aide to text, worrying: "Republicans get to frame it as single payer vs their alternative in prime time.") — Gabriel Debenedetti (@gdebenedetti) September 21, 2017

Dem source: "This is exactly the debate Graham & Cassidy want to have. Sanders is looking out for himself rather than being a team player" https://t.co/o8wQ7sZqFN — Frank Thorp V (@frankthorp) September 21, 2017

And journalists in general suggested that fielding Sanders was a bad idea for Democrats.

Graham and Cassidy want this to be Rs vs. Ds — not Rs vs. Rs. And Sanders on stage helps them make it about single payer, his true love. https://t.co/5zaOF1hsvL — Sahil Kapur (@sahilkapur) September 21, 2017

Why on earth would Democrats want to feed into the idea this is somehow a binary choice between single payer (Bernie) and Graham/Cassidy??? https://t.co/WVp3ddFnu7 — Garrett Haake (@GarrettHaake) September 21, 2017

Dems already worrying this will allow Rs to frame bill as alt to single-payer. Quiet griping that Sanders jumped gun likely to grow louder. https://t.co/vhPolFkGZx — Alex Seitz-Wald (@aseitzwald) September 21, 2017

The debate will be broadcasted live from Washington, D.C. CNN’s Jake Tapper will moderate, alongside CNN chief political correspondent Dana Bash.