A Charles County senator stepped up his criticism of Senate President Bill Ferguson on Monday night, saying his fellow Democrat was not fit to lead the chamber.

Sen. Arthur Ellis said Ferguson’s decision to block a plan to further gerrymander Maryland’s congressional maps in favor of Democrats disqualified him from being Senate president.

“That is shameful,” Ellis said of Ferguson’s stance. “How could any of my colleagues say that it’s OK?”

Ferguson’s office did not return a request for comment Monday.

Four days ago, Ellis staged a one-man protest on the Senate floor, demanding that Ferguson allow a vote on the redistricting proposal.

The plan, which the House passed overwhelmingly, is one of Gov. Wes Moore’s top priorities. It would target GOP Rep. Andy Harris and his Eastern Shore district.

Moore personally called Ellis after his Senate speech on Thursday to thank him. The governor has since lavished praise on Ellis — on cable news shows, on social media and in a statement issued by his office.

Ellis’ call for Ferguson’s job underscores the immense tension between leading members of his own party when it comes to redistricting.

For months, Ferguson and Moore have been at odds over mid-cycle redistricting. Widely considered a Democratic darling and 2028 hopeful, Moore has mounted an intensifying pressure campaign on Ferguson.

Moore has appeared next to leading Democrats in Washington and on cable news and party-friendly podcasts to call for Ferguson to allow the redistricting plan to come to a vote. The nation’s only Black governor, he’s said that those who oppose redistricting are trying to silence Black leadership and diminish Black voting power.

That pressure is starting to reveal strain in Moore and Ferguson’s working relationship. In January, before a meeting to discuss Moore’s proposed budget, Ferguson confronted the governor with a printout of a campaign finance report for Ferguson’s primary opponent.

Ferguson highlighted that the first two donations listed on his opponent’s report were employees in Moore’s office.

The pressure exerted by the Senate president and governor is manifesting as a fractured, albeit slightly, Democratic caucus.

Sen. Clarence Lam of Howard County joined Ellis on Monday for a news conference in a Senate hallway.

While Lam has long been known to support redistricting, he’s the only other senator so far to take a public stance and appear with Ellis.

“The movement has grown,” Ellis said. “It’s doubled.”

Lam avoided criticizing Ferguson and focused on the merits of redistricting. He cited turmoil at the federal level — cuts to the government workforce, withholding state funding, a lack of willingness to hold President Donald Trump accountable — as reason to redraw Maryland’s congressional maps so that all eight districts favor Democrats.

Redistricting would “level the playing field to make sure that, when it comes to Congress, they have an ability to do their job to hold this administration accountable,” Lam said.

Ellis did not shy away from criticizing his fellow Democrats. He said people call him to ask, “What the hell is going on in Annapolis?” and to ask why he, as a Black senator, is sitting on the sidelines and watching “a white guy go against a Black governor.”

“I am not part of this mess. I am not part of this coma that’s happening in Annapolis,” Ellis said.

He also suggested Ferguson was in bed with Republicans.

“The Republicans are happy that the Democratic president [Ferguson] is trying to kill redistricting in Maryland,” Ellis said as a staffer handed out printed packets to the press of social media posts from Republicans agreeing with Ferguson’s stance.

Ellis is weighing a congressional run to replace the retiring Rep. Steny Hoyer, but he bristled at the notion that he would speak up on such an issue for political gain.

“I’ve always been outspoken,” Ellis said, adding that he speaks for his constituents. “They sent me here, gave me this job, to speak up for them with that loud, unflinching voice to say the difficult things.”

He added some frank electoral advice for his Senate colleagues. Ellis said those who oppose Moore’s redistricting plan are preparing to commit “political suicide” in the Democratic primaries. In Maryland, only voters for a registered party can vote in that party’s primary elections.

“Before they can be voted in by independents and Republicans and everyone else, they have to meet the party activists,” Ellis said. “And the party activists are mad as hell.”