The two Democrats who oppose changing the Senates filibuster rules on Tuesday begged Republicans to support a bipartisan commission to investigate the Jan. 6 riot in the U.S. Capitol.

In a joint statement, Sens. Joe Manchin (D-W.Va.) and Kyrsten Sinema (D-Ariz.) called the creation of a commission critical to prevent such an attack from occurring again.

We implore our Senate Republican colleagues to work with us to find a path forward on a commission to examine the events of January 6th, the two senators said in the statement.

If not enough Republicans support the bill, Manchin and Sinema will face even greater pressure to join with their Democratic colleagues in junking the Senates legislative filibuster, which requires a supermajority of 60 senators to bypass.

The House passed a bill last week that would set up a 10-member panel of outside experts, with five appointed by Democrats and five by Republicans, to investigate what went wrong on Jan. 6 and recommend policy changes to prevent it from happening again.

Thirty-five Republicans supported the House bill, which had been written by Reps. Bennie Thompson (D-Miss.) and John Katko (R-N.Y.), the top lawmakers on the Homeland Security Committee.

But Senate Republicans broadly oppose the bill, mostly on the grounds that existing congressional investigations are sufficient to probe the attack, even though Congress has previously set up special commissions that complemented its own committee work.

Republicans also fear that a monthslong investigation would anger former President Donald Trump and hurt them politically during next years midterm elections. Trump has lashed out at the commission in recent days, saying that unless the murders, riots, and fire bombings in Portland, Minneapolis, Seattle, Chicago, and New York are also going to be studied, this discussion should be ended immediately.

Addressing the matter at his weekly press conference, Senate Minority Leader Mitch McConnell (R-Ky.) said he views the Jan. 6 commission as a purely political exercise and that he would rather voters focus on the Biden administration and not events of the past.

Democrats need at least 10 Republicans to join them in advancing the bill to the floor, which could receive a vote as early as this week. Its difficult to see that happening at the moment.

Only a handful of Republican senators who voted to convict Trump over the Jan. 6 attack have expressed openness to the measure. Some, like Susan Collins of Maine and Mitt Romney of Utah, say they support the concept in general but are asking for further changes to the structure of the commission. Sen. Lisa Murkowski (R-Alaska), meanwhile, told HuffPost she would support the bill.

But other GOP senators who voted to convict Trump over the Jan. 6 attack are outright opposed, like Sens. Richard Burr (N.C.).

Sen. Bill Cassidy (R-La.), who is undecided, seemed to rebut McConnells argument about Democrats turning the Jan. 6 commission into a partisan expedition.

If they wish to have a political weapon, itd be easy for [Senate Majority Leader Chuck Schumer] and [House Speaker Nancy Pelosi ] to each appoint their own committees and run now as long as they want to. So it seems like in that regard, this would be a better approach. Because certainly if you could time-limit it, it would be a better approach.

If senators cant agree on a path forward, it may become the first bill Republicans filibuster in Congress.

Republicans have been publicly effusive in their praise for Manchin and Sinema over their stance on preserving the filibuster, which they argue is critical to the institution of the Senate as a whole. Some GOP-aligned groups have even run ads thanking the two Democrats in their home states.

Manchin, however, said he wouldnt support blowing up the filibuster even if Republicans block the Jan. 6 commission bill.

That is extremely frustrating and disturbing. ... I would like to think he loves this institution, Manchin told reporters when asked about McConnells comments.

Filibuster opponents are watching closely as the debate over the Jan. 6 commission heats up and as the bipartisan talks regarding an infrastructure overhaul appear to be hitting a wall. Republicans are trading offers with the White House, but the two sides are still very far apart on reaching a deal on a bipartisan infrastructure and jobs bill as proposed by President Joe Biden.

If Sen. McConnell and his caucus are willing to use the filibuster to block a bipartisan bill to form a bipartisan commission to investigate an attack on the United States Congress, then it should be clear that there is absolutely nothing they will work with Democrats on in good faith, said Eli Zupnick, a spokesman for advocacy group Fix Our Senate. Democrats must eliminate the filibuster as a weapon that Sen. McConnell can wield to block every attempt to defend and restore our democracy.

Several Republicans said they were looking forward to an amendment by Collins that would give the Republican-appointed members of the commission more say on the commissions staffing. Manchin called the possible changes very reasonable.