A group of staffers serving freshman Rep. Jeff Van Drew (D-N.J.) resigned Sunday ahead of his expected switch to the Republican Party over the impeachment inquiry. Driving the news: Van Drew, a moderate Democrat, said this month that he planned to oppose articles of impeachment against President Trump. On Saturday, a White House official told Axios' Jonathan Swan that Van Drew planned to switch parties over the matter. What they're saying: A sixth staffer confirmed to NBC News just before midnight that she's also leaving Van Drew's office. Democratic Congressional Campaign Committee chair Rep. Cheri Bustos offered to help the staffers find new jobs in a tweet sharing a report of the news by Politico, which broke the story.Read the resignation letter: Go deeper: Democrats expect handful of defections on impeachment vote Editor's note: This article has been updated with new details of the report of a sixth staffer quitting and Bustos' offer.