A former leadership staffer will brief Senate Democrats during a closed-door caucus lunch Friday about how they could potentially change the upper chamber's rules as they renew their focus on passing voting rights legislation.

Senate Majority Leader Charles Schumer (D-N.Y.) said Marty Paone, a former secretary of the Democratic conference and parliamentary expert, briefed a group of Senate Democrats Thursday night and will speak during their caucus lunch Friday.  

"Last night a number of my colleagues and I met with Marty Paone, a Senate rules expert who worked under past leadership, including Robert C. Byrd, about how we can restore the Senate so it can work the way our founders intended," Schumer said.

"Later today, Marty will join with Senate Democrats at our Caucus meeting to continue this very important conversation," Schumer added.

Democrats have ramped up their public focus on potential changes to Senate rules with an eye toward getting voting rights bills passed as they face stumbling blocks to meeting their goal of passing President Biden's Build Back Better legislation by Christmas. 

The Senate is poised to leave for the year without voting rights or Build Back Better completed and without a clear path toward finishing either. 

A growing number of Democratic senators have endorsed changes to the 60-vote hurdle required for most legislation to pass the Senate. Sen. Maggie Hassan (D-N.H.), who is up for reelection in 2022, became the latest on Thursday night to support nixing the roadblock for voting rights legislation.  

"A set of arcane Senate rules are being used as an excuse not to act. This cannot stand. We must change the rules to allow a simple majority of this body ... to pass laws that will protect the right to vote and protect American democracy," Hassan said during a speech from the Senate floor on Thursday night.

Republicans have blocked several voting rights or elections bills, fueling support within the caucus for changing the rules. A group of senators, including Sens. Angus King (I-Maine), Tim Kaine (D-Va.) and Jon Tester (D-Mont.), have been leading talks within the caucus to come up with a potential rules change proposal. 

But to change the rules without GOP votes, Democrats would need total unity from within their entire 50-vote caucus. 

Sens. Joe Manchin (D-W.Va.) and Kyrsten Sinema (D-Ariz.) have opposed getting rid of the 60-vote legislative filibuster. Though Manchin has been involved in discussions, he's also said rules change discussions have to be bipartisan.