Inside the Senate GOP's push to ignore the parliamentarian

• How and when exactly this will all go down is still unclear.

Driving the news: Barrasso and Senate Environment and Public Works Chair Shelley Moore Capito (R-W.Va.) gave presentations at the lunch, arguing for moving forward with the CRA to undo a California waiver that would eventually ban gas-powered vehicles, attendees tell Axios.

• At least one key player backed them up: Rules Chair Mitch McConnell (R-Ky.), a vocal defender of Senate precedent and the filibuster, sources said.
• Most GOP senators expressed support, though some still have questions.
• Sen. Susan Collins (R-Maine) told reporters that she would be meeting with Capito to discuss the move today. "I certainly support the intent of it. There's some procedural issues," she said.

Between the lines: Democratic leaders are warning already that such a move would amount to a "nuclear option," blowing up how the Senate can use the Congressional Review Act to undo all kind of policies.

• "Republicans are now considering overruling Ms. MacDonough, essentially going nuclear and throwing out the rule book in order to get their way," Sen. Alex Padilla (D-Calif.) wrote in a Tuesday Wall Street Journal op-ed.

• Republicans argue it is a unique situation, that doesn't amount to actually overruling the parliamentarian.
• Barrasso in particular has been leading the charge. "Thankfully the bureaucrats at the GAO can't dictate the actions of the U.S. Senate or the will of the voters," he wrote in an earlier WSJ op-ed. "My colleagues can safely disregard the office's decision in this case."