(CNN) Republican Rep. Elise Stefanik of New York, a member of the House Intelligence Committee, has played a key role in this week's public impeachment hearings, ardently defending President Donald Trump, sparring with Democrats on the committee and earning praise from the White House.
"These hearings are not about tweets, they are about impeachment of the President of the United States," Stefanik said at a contentious press briefing following Friday's hearing. "This is a constitutional matter. You can disagree or dislike the tweet, but we are here to talk about impeachment and nothing in that room today and nothing in that room this week nothing rises to the level of impeachable offenses."
Stefanik herself told CNN earlier on Friday that she disagreed with the tweet in question — one in which Trump attacked former US ambassador to Ukraine Marie Yovanovitch, which Democrats argue could amount to witness tampering — but it didn't sway her from standing squarely behind the President throughout the hearing.
"I disagree with the tweet. I think Ambassador Yovanovitch is a public servant, like many of our public servants in the foreign service," she said.
During the hearing, Stefanik focused on the whistleblower at the heart of the impeachment probe and hit Democrats for not pursuing testimony from the anonymous intelligence community professional.
Democrats say the whistleblower's testimony is unnecessary given the President's public statements about his interactions with Ukraine and the information brought by witnesses who have already come forward.
For some congressional observers, the impeachment inquiry may be their first introduction to congresswoman, but she's been making waves on Capitol Hill for nearly five years.
Stefanik, 35, was first elected in 2014, when she was 30 years old, becoming -- at the time -- the youngest woman ever elected to Congress.
She represents New York's 21st congressional district. A Harvard graduate, Stefanik previously was an aide to former president George W. Bush, later working for then-Republican presidential nominee Mitt Romney -- now a US senator from Utah -- and his running mate Paul Ryan during the presidential campaign in 2012.
In the wake of the 2018 midterm elections, when it became clear that the House GOP Conference would have only 13 women in its ranks, Stefanik has worked to recruit and raise money for female Republican candidates to run for Congress.
Stefanik is a moderate, and while she is supportive of Trump, she has also been openly critical of some of his policy positions, like the decision to withdraw from the Paris Climate Agreement.
She said that climate change "is a serious threat that must be addressed by our entire global community, and the United States should continue to lead," in 2017, calling the choice to withdraw from the pact "misguided" and saying it "harms the ongoing effort to fight climate change while also isolating us from our allies."
On most issues, Stefanik is a reliable Republican vote, although she split with most of her colleagues to vote against the GOP tax bill in late 2017.
As the only Republican woman on the Intelligence Committee, she stands out among her GOP colleagues.
Stefanik can be unflinching when confronting sexism. During the closed-door impeachment inquiry deposition of Lt. Col. Alexander Vindman, the top Ukraine expert on the National Security Council, a moment stood out: When Stefanik began her questioning, Vindman's lawyer, Michael Volkov, interjected with, "First off, I don't know who you are," asking her to identify herself, according to the transcript of the deposition.
"I'm on the House Intelligence Committee," Stefanik said. "I'm from New York. I'm a third term member."
"I get asked this a lot," she added.
"Oh, that's good," Volkov said.
"No, it's not good," Stefanik responded. "But I will continue my line of questioning."
She later tweeted about the interaction, saying the question had been asked because "I was the only young woman at the table.
"The attorney assumed I was staff," she wrote. "And every single person in the room knew it."