Senator Lisa Murkowski, a Republican from Alaska, speaks during a Senate Health, Education, Labor and Pensions Committee hearing on efforts to get back to work and school during the coronavirus disease (COVID-19) outbreak, in Washington, D.C., June 30, 2020.Al Drago | Pool | ReutersGOP Sen. Lisa Murkowski of Alaska said on Friday that President Donald Trump should immediately resign, offering the harshest rebuke from a senator in Trump’s own party since a mob of his supporters invaded the U.S. Capitol on Wednesday.”I want him to resign. I want him out. He has caused enough damage,” Murkowski, known as a moderate in her party, told the Anchorage Daily News. The White House did not respond to a request for comment.”I think he should leave. He said he’s not going to show up. He’s not going to appear at the inauguration. He hasn’t been focused on what is going on with Covid,” she added. “He’s either been golfing or he’s been inside the Oval Office fuming and throwing every single person who has been loyal and faithful to him under the bus, starting with the vice president.””He doesn’t want to stay there. He only wants to stay there for the title. He only wants to stay there for his ego. He needs to get out. He needs to do the good thing, but I don’t think he’s capable of doing a good thing,” Murkowski said.Murkowski’s comments come as Democrats are gearing up for an unprecedented second impeachment in the wake of the D.C. riot and the president’s continued refusal to retract baseless claims of widespread election fraud. At least five people died in the attack, which was spurred by Trump’s lie that the election was stolen by President-elect Joe Biden and Democrats.Murkowski said that Trump was responsible for the violence.”I will attribute it to the president,” Murkowski said. She noted that even after Pence said that he did not have the authority to overturn the election, Trump “still told his supporters to fight” at a rally that preceded the riot.”How are they supposed to take that? It’s an order from the president. And so that’s what they did,” Murkowski said. “They came up and they fought and people were harmed, and injured and died.”Murkowski’s comments come as House Speaker Nancy Pelosi, D-Calif., and Senate Minority Leader Chuck Schumer, D-N.Y., prepare for a potential impeachment. The Democratic leaders have called for Trump’s Cabinet to remove him through the 25th Amendment, but that prospect is unlikely.Reps. David Cicilline, D-R.I.; Ted Lieu, D-Calif., and Jamie Raskin, D-Md., plan to introduce articles of impeachment on Monday, NBC News has reported.So far, only one other Republican senator has expressed even tentative support for impeachment. Sen. Ben Sasse, R-Neb., told CBS on Friday that he would “definitely consider whatever articles they might move.””As I’ve told you, I believe the president has disregarded his oath of office … What he did was wicked,” Sasse said.Murkowski did not explicitly address impeachment in the comments published by the Anchorage Daily News. A spokesperson for Murkowski did not respond to an email seeking elaboration.In the interview, the Alaska senator also suggested that she might be rethinking her membership in the Republican Party.”I will tell you, if the Republican Party has become nothing more than the party of Trump, I sincerely question whether this is the party for me,” she said.Democrats are set to gain control of the Senate by a slim margin of 50-50, with Vice President-elect Kamala Harris able to cast tiebreaking votes.Subscribe to CNBC Pro for the TV livestream, deep insights and analysis on how to invest during the next presidential term.