snowball's chance in hell

“You don’t have a snowball’s chance in hell of getting it through the House, because we took the border issue and we didn’t address it the way it should have been,” Mr. Graham said.

Nikki Haley may not have a snowball's chance in hell of winning the Republican presidential nomination but she's decided she's not going to go quietly.

Fortunately, Trump 2.0 has a snowball’s chance in hell of becoming president.

“And maybe there’s this snowball’s chance in hell that maybe he wouldn’t go to the Dodgers or Giants and maybe come up here, so I kept my mouth shut.”

Of course this has a snowball’s chance in hell for passage, because the result will be the end of many lifelong congressional careers.