A progressive group is targeting two Senate Democrats and an independent senator who voted to confirm some of President Donald Trump’s judicial nominees, promising to spend more than $1 million in hopes of pushing congressional Democrats to take a stronger stand against the Republican president.

In a weeklong advertising campaign that began on Wednesday, Demand Justice is targeting only senators who aren’t up for reelection next year: Democrats John Fetterman of Pennsylvania and Maggie Hassan of New Hampshire, along with independent Angus King of Maine, who caucuses with Democrats.

But the group’s president, Josh Orton, said the blitz is only an opening salvo. He threatened an escalation targeting more imminently vulnerable lawmakers and those with presidential ambitions unless they “find their moral compass, and stand up to Trump.”

“We want to change Senate Democratic behavior so that they begin acting in a more moral way and in a more politically expedient way,” Orton said.

The push comes after eight members of the Senate Democratic caucus — including Fetterman, Hassan and King — joined with Republicans to end a government shutdown, a move that angered large swaths of the party’s base. The party is wrestling over the best strategy to fight what many Democrats see as Trump’s authoritarian ambitions while plotting to bounce back from major losses in 2024.

In confirmation hearings, Trump’s second-term judicial nominees have avoided acknowledging that he lost the 2020 campaign or that the Jan. 6, 2021, attack on the U.S. Capitol was a violent insurrection. Democrats shouldn’t give bipartisan cover to judges who are not “able to answer these simple questions of fact,” Orton said.

The Democratic base is clamoring for its representatives to aggressively challenge Trump, who has pushed the boundaries of presidential power to new heights since returning to the White House in January. Democratic leaders, meanwhile, are grappling with the limits of their power in Washington, where Republicans control both chambers of Congress and the White House.

Fetterman is a frequent target of the left over his staunch support for Israel in the Gaza war and his willingness to buck the majority of his party. He defended his voting record last month, telling CBS News he’s voted overwhelmingly with the rest of the Democrats.

“If Democrats have a problem with somebody that votes 91% of the same times as you are — more than nine out of 10 times — then maybe our party has a bigger problem,” Fetterman said.

Hassan said she voted to reopen the government, despite the backlash on the left, because many of her constituents were suffering and it was unlikely Republicans would agree to a better deal. She said she supported some of Trump’s executive branch nominees “who are qualified or acting in good faith.”

King was the lone member of the Democratic Caucus to vote to confirm a federal judge in Missouri who, as a lawyer, had worked on cases challenging abortion rights. He later said the vote was “a mistake.”