Lisa Ann Murkowski (born May 22, 1957) is an American attorney and politician serving as the senior United States senator representing Alaska, having held that seat since 2002. She is the Senate's second-most senior Republican woman, after Susan Collins of Maine. She became dean of Alaska's Congressional delegation upon Representative Don Young's death.

Murkowski is the daughter of former U.S. senator and governor of Alaska Frank Murkowski. Before her appointment to the Senate, she served in the Alaska House of Representatives and was elected majority leader. She was controversially appointed to the Senate by her father, who resigned his seat in December 2002 to become governor of Alaska. She completed her father's unexpired Senate term, which ended in January 2005, and became the first Alaskan-born member of Congress.

Murkowski ran for and won a full term in 2004. After losing the 2010 Republican primary to Tea Party candidate Joe Miller, she ran as a write-in candidate and defeated both Miller and Democrat Scott McAdams in the general election. She is the second U.S. senator (after Strom Thurmond in 1954) to be elected by write-in vote. She was elected to a third term in 2016 and a fourth term in 2022, running as a Republican.

Murkowski was vice chair of the Senate Republican Conference from 2009 to 2010, chair of the Senate Energy and Natural Resources Committee from 2015 to 2021, and has been vice chair of the Senate Indian Affairs Committee since 2021.

She is often described as one of the Senate's most moderate Republicans, and a crucial swing vote. According to CQ Roll Call, she voted with President Barack Obama's position 72.3% of the time in 2013, one of only two Republicans to do so over 70% of the time. In recent years, she opposed Brett Kavanaugh and supported Ketanji Brown Jackson in their respective nominations to the Supreme Court. On February 13, 2021, she was one of seven Republican senators to vote to convict Donald Trump of incitement of insurrection in his second impeachment trial, for which she was censured by the Alaska Republican Party.