If you too are disappointed in Sen @BillCassidy #GrahamCassidy let them know it - call (202) 224-3121 pic.twitter.com/eswlh6BaoV&mdash; Jimmy Kimmel (@jimmykimmel) September 20, 2017 Late-night comedian Jimmy Kimmel skewered the new Republican healthcare plan, a potentially devastating development as Senate GOP leaders struggle for support ahead of a&nbsp;possible vote next week.Kimmel&nbsp;waded into the healthcare debate earlier this year&nbsp;when he choked up on TV&nbsp;recounting&nbsp;his newborn son's heart condition &mdash;&nbsp;and the high costs&nbsp;of healthcare that he can pay, but he knows other Americans cannot.The "Jimmy Kimmel Live" host&nbsp;has become one of the most prominent celebrities to publicly advocate&nbsp;preserving&nbsp;Obamacare's insurance protections &mdash;&nbsp;so much so that Republicans themselves have aspired to meet "the Jimmy Kimmel test."It says that patients like the child born with a congenital disease would get the care they need, with no caps on insurance coverage for pre-existing conditions, regardless of costs.On Monday night, Kimmel&nbsp;said the new bill from Sen. Lindsey Graham (R-S.C.) and Sen. Bill Cassidy (R-La.) &mdash;&nbsp;a one-time guest on the show who coined the Kimmel test phrase&nbsp;&mdash;&nbsp;failed&nbsp;the standard."This new bill actually does pass the Jimmy Kimmel test but a different Jimmy Kimmel test," the comedian said in his opening monologue."With this one, your child with the pre-existing condition will get the care he needs if, and only&nbsp;if, his father is Jimmy Kimmel. ... ," he said.&nbsp;"Not only did Bill Cassidy fail the Jimmy Kimmel test, he failed the Bill Cassidy test."He said: "This guy, Bill Cassidy,&nbsp;just lied to my face."The reaction was swift and fierce, especially because Kimmel tweeted the Capitol switchboard number for viewers to call their senators urging a "no" vote.Democrats and others opposed to the new bill quickly shared the message, ensuring phone lines lit up at Congress.Cassidy, a medical doctor who has worked tirelessly on the new bill, mounted a vigorous defense Wednesday&nbsp;and said Kimmel was mistaken."I am sorry he does not understand," the senator said on CNN. "Under Graham-Cassidy-Heller-Johnson, more people will have coverage, and we protect those with pre-existing conditions."Experts analyzing the just-released bill, which Republicans are trying to pass before a Sept. 30 deadline, say it would&nbsp;more likely cut coverage for millions of Americans.Under the plan, states that expanded Medicaid coverage for lower-income Americans with Obamacare would see their funding reduced and distributed more evenly with those that did not.States also would have more leeway to apply for waivers from the kinds of Obamacare protections against spending caps and lifetime limits that were a cornerstone of the Affordable Care Act.Republicans have not yet secured the 50 votes needed from their slim 52-seat majority for passage.Key GOP senators who opposed an earlier overhaul &mdash;&nbsp;Sen. John McCain (R-Ariz.), Sen. Susan Collins (R-Maine) and Sen. Lisa Murkowski (R-Alaska) &mdash;&nbsp;have not said whether they will support the new bill.Sen. Rand Paul (R-Ky.) has said he will oppose it, and others may join him.Kimmel's monologue could prove pivotal in influencing the&nbsp;debate.