Staff members who fled Van Drew’s office said earlier this week that it was ultimately the congressman who left them no choice.

“Sadly, Congressman Van Drew’s decision to join the ranks of the Republican Party led by Donald Trump does not align with the values we brought to this job when we joined his office,” according to a letter from several aides, which was first obtained by POLITICO. The staffers added that “Trump Republicans” have worked to “aid and abet Trump as he shreds the Constitution and tears the country apart.”

The Democratic Congressional Campaign Committee has vowed to temporarily employ them until they find new offices on Capitol Hill.

Van Drew, who vowed to run for reelection, repeatedly declined to confirm reports that he’s already decided to shed his Democratic affiliation and join the GOP, following a Friday meeting with President Donald Trump.

"People kind of know that I'm going in a direction," Van Drew said. "But I haven’t announced anything."

He said he would announce his intentions soon and he was given “no commitments” for committee assignments or other benefits to induce him to switch sides.

Rather, Van Drew said, if he does decide to jump to the Republican Party, it “will be based upon ultimately reconciling the philosophy that I feel in my heart.”

News of Van Drew’s party switch came at a sensitive moment for Democrats, who are moving to impeach Trump on Wednesday over allegations he pressured Ukraine to investigate his political rivals and then obstructed the ensuing congressional probe. Van Drew has long argued that Democrats’ impeachment case is weak and was one of just two members of the caucus to oppose a decision to open the impeachment inquiry.

Even as Van Drew declined to publicly confirm his exit from the party, his colleagues were taking steps to prepare for it.

The Blue Dog Coalition, a group of centrist Democrats, voted Tuesday afternoon to eject Van Drew from the group, according to lawmakers and aides. The coalition of moderate Democrats voted unanimously to suspend the New Jersey freshman “indefinitely,” according to one person present.

“Per our by laws, which require all members to be a member of the Democratic Party, Congressman Van Drew is no longer a member of the Blue Dog Coalition,” Rep. Stephanie Murphy (D-Fla.), co-chair of the Blue Dog Coalition, said in a statement.

A day earlier, Murphy delivered a letter to Van Drew informing him that he was “no longer eligible for membership,” though he was invited to come address the group during their Tuesday meeting. Van Drew did not attend.

Asked about the group’s decision, Van Drew said they were “assuming I’m going to change.”

"They are doing that on the basis of the fact that it is a Democratic — and a good one — organization, and you could not be a member if you were to change,” he said.

Another group that Van Drew belongs to — the bipartisan Problem Solvers Caucus — will also have to do some rearranging when he joins the GOP. The group requires an equal number of members from both parties, so Van Drew will need to be readmitted to the caucus at the same time that a new Democrat is brought into the fold, according to one lawmaker familiar with the matter.

Van Drew repeatedly declined to say whether he would appear publicly with Trump. “You’ll find out when I appear or don’t appear,” he said, though such an event is expected.

Asked whether his contention just days earlier that he would not switch parties was a lie, Van Drew demurred.

“I don’t know if you consider it a lie,” he said. “I think you would consider it a hope and a wish.”

Sarah Ferris contributed to this report.