Just six GOP senators broke ranks with the party to support advancing the January 6 commission, including Bill Cassidy of Louisiana, Susan Collins of Maine, Lisa Murkowski of Alaska, Rob Portman of Ohio, Mitt Romney of Utah and Ben Sasse of Nebraska.

Eleven senators were not present for the vote, including nine Republicans. A spokesperson for Republican Sen. Patrick Toomey said he missed the vote due to a “family commitment” but he “would have voted in favor of the motion.”

“We have a mob overtake the Capitol, and we can’t get the Republicans to join us in making historic record of that event? That is sad,” Democratic Sen. Dick Durbin said ahead of the vote. “That tells you what’s wrong with the Senate and what’s wrong with the filibuster.”

The formation of a January 6 commission, which would be modeled off the probe that took place after the 9/11 attacks, has been delayed for months over negotiations about the panel’s make-up and scope.

Some Republican lawmakers, including House Majority Leader Kevin McCarthy, oppose the bill because they want the committee to also investigate far-left forms of political violence. Other lawmakers, such as Senate Minority Leader Mitch McConnell, have slammed the bill as a “purely political exercise.”

“I do not believe the additional, extraneous, commission that Democratic leaders want would uncover crucial new facts, or promote healing. Frankly, I do not believe it is even designed to do that,” McConnell said on the Senate floor ahead of Thursday’s vote.

The bill would establish a 10-person committee, five commissioners would be appointed by Democrats and five commissioners appointed by Republicans. It would also mandate that both sides sign-off on any subpoenas during the investigation.

The commission would be charged with studying the facts and circumstances of the U.S. Capitol attack as well as the influencing factors that may have provoked it. Five people died during or shortly after the riot, where a mob of pro–Donald Trump supporters sought to disrupt the congressional certification of Joe Biden’s electoral victory.

The House of Representatives finally passed legislation to create a panel on May 16. The lower chamber voted 252–175 in favor of the commission, with 35 House Republicans breaking with the party to support it.

But in the Senate, which is evenly split 50-50, Democrats needed the support of at least 10 Republicans to move to the commission bill—sparking new debate over whether Democrats should change the filibuster rules and lower the threshold to 51 votes to pass legislation.

Here are the Senate Republicans who did not vote in favor of moving forward with the January 6 commission bill.

John Barrasso of WyomingJohn Boozman of ArkansasShelley Moore Capito of West VirginiaJohn Cornyn of TexasTom Cotton of ArkansasKevin Cramer of North DakotaMike Crapo of IdahoTed Cruz of TexasSteve Daines of MontanaJoni Ernst of IowaDeb Fischer of NebraskaLindsey Graham of South CarolinaChuck Grassley of IowaBill Hagerty of TennesseeJosh Hawley of MissouriJohn Hoeven of North DakotaCindy Hyde-Smith of MississippiRon Johnson of WisconsinJohn Kennedy of LouisianaJames Lankford of OklahomaMike Lee of UtahCynthia Lummis of WyomingRoger Marshall of KansasMitch McConnell of KentuckyJerry Moran of KansasRand Paul of KentuckyMarco Rubio of FloridaRick Scott of FloridaTim Scott of South CarolinaDan Sullivan of AlaskaJohn Thune of South DakotaThom Tillis of North CarolinaTommy Tuberville of AlabamaRoger Wicker of MississippiTodd Young of Indiana