WASHINGTON — New Jersey Rep. Jeff Van Drew did what he said he would do, and it almost surely cost him his longtime political home in the Democratic Party: He voted against impeaching President Donald Trump.

Van Drew voted against both articles of impeachment late Wednesday, disagreeing with the vast majority of his Democratic colleagues, who maintained that Trump abused his power and obstructed Congress. He was one of only two Democrats to vote against the former, and one of only three to vote against the latter.

His votes were expected, but still capped months of controversy for the South Jersey congressman, whose vocal opposition to impeachment enraged Democratic leaders and activists, and prompted plans for him to switch parties and seek reelection as a Republican.

“As I’ve said all along, I’m going to vote no,” Van Drew told a Fox News reporter just hours before the impeachment vote.

Though Van Drew cast his votes Wednesday as a Democrat, he sat on the Republican side of the House floor as lawmakers formally debated articles of impeachment against Trump. Van Drew also sided with Republicans on some early procedural votes as his soon-to-be GOP colleagues tried to slow the daylong march toward a formal impeachment vote.

“I’m glad to be sitting by @CongressmanJVD and new member of GOP,” Nebraska Republican Rep. Don Bacon said on Twitter at one point.

Van Drew was one of only two House Democrats to vote against the impeachment inquiry into the president’s dealings in Ukraine in October, a stance he touted in TV appearances that drew the attention and praise of Trump himself.

Revelations of his planned defection have drawn fierce attacks from Democrats, and skepticism from Republicans wary of his voting record and his longstanding ties to the New Jersey’s Democratic machine.

“Jeff Van Drew has chosen his political career over our Constitution,” New Jersey Gov. Phil Murphy said in a recent statement. “Despite knowing full well that the president has abused the powers of his office, Congressman Van Drew is now willing to enable Donald Trump just to try to salvage his own election.”

On Dec. 11, Van Drew learned from an internal poll just how much his stance on impeachment had harmed his prospects in a Democratic primary. He proceeded to cut off contact with key allies, and by Friday was at the White House to finalize his plans to become a Republican. He finally broke his silence on the matter Tuesday.

“I’m not discussing any of that now. There will be a time,” he said. “I’m reevaluating my life and my thoughts.”

At least eight members of his House staff have resigned, along with all three members of his campaign staff. Six of his former aides will be hired by New Jersey Democratic Rep. Frank Pallone to work on the House Committee on Energy and Commerce, which Pallone chairs, according to sources familiar with the matter.

Local Republicans are hardly welcoming Van Drew with open arms. All three Republican candidates who were running for his seat will stay in the race, and local party leaders and activists have been lukewarm at best in their receptions.

“He will have to prove he is with us on more than just the issue of impeachment,” said Jacci Vigilante, chair of the Gloucester County GOP.

Trump has fired off a couple of tweets lauding Van Drew. But the president has yet to formally endorse him, and it remains to be seen how hard he would campaign for the longtime Democrat in a Republican primary.

Staff writer Jonathan Tamari contributed to this article.