Sarah Matthews, an ex-spokesperson for former President Trump, said Monday that she is backing Vice President Harris to ensure that the former president “never steps foot in the Oval Office again. Matthews, in an interview with MSNBC's Andrea Mitchell, said speaking out against her former boss wasn't enough. She added that it was important for her to "take that next step and show that it's okay to put partisanship aside and prioritize your country.” “And so, that's why I was willing to endorse Kamala Harris, because I believe that we need to do everything we can to ensure that Donald Trump never steps foot in the Oval Office again,” she told Mitchell. Matthews joined former Rep. Liz Cheney (R-Wyo.) and her fellow ex-Trump White House officials Alyssa Farah Griffin and Cassidy Hutchinson at an event last week in battleground Pennsylvania. All four women, who used to be close allies to the former president, have emerged as some of the GOP presidential nominee's loudest critics. Like Cheney, Matthews has expressed that she believes Trump is a threat to democracy, saying in late 2022 “that [the Jan. 6 Capitol riots] showed that, and that was part of my reason for resigning." When pressed on whether she's faced threats or harassment since leaving the Trump administration, Matthews confirmed that she had. She said she calculated and the risk, and determined it was worth it to speak out against the GOP nominee. “I know that there's harassment and backlash in terms of my career prospects, and [I] probably won't be able to have a career in Republican politics, at least in the current makeup of the Republican Party,” Matthews said Monday. “But for me, what scared me more was the idea of a second Trump term, and if I sat on the sidelines of history and didn't say anything and speak out and know that I could’ve used my voice to help dissuade people from voting for him again,” she added. “And, so that for me, it was an easy calculation.” The Hill has reached out to the Trump campaign for comment.