In 2020, a special election was held to determine who would serve the remainder of McCain's unexpired Senate term; McSally was defeated by Democratic nominee Mark Kelly.

[2] During an interview with The Wall Street Journal in April 2018, McSally alleged her track and field coach pressured her into a sexual relationship during her senior year at the Catholic girls' school.

[6][2] She then earned a master's degree in public policy from Harvard University's John F. Kennedy School of Government and proceeded to pilot training.

[8] McSally then completed Replacement Training Unit for the A-10 Thunderbolt II at Davis–Monthan Air Force Base and was assigned to an operational A-10 squadron that deployed to Kuwait in January 1995.

In a 60 Minutes interview broadcast on CBS on January 20, 2002, she described the discrimination she experienced under the policy: "I have to sit in the back and at all times I must be escorted by a male ... [who], when questioned, is supposed to claim me as his wife," she said.

[16][17] In 2002, Congress passed legislation prohibiting anyone in the military from "requiring or encouraging servicewomen to put on abayas in Saudi Arabia or to use taxpayers' money to buy them.

McSally led on election night by a few hundred votes, but the race was deemed too close to call due to a large number of provisional ballots.

[37] According to The Arizona Republic, McSally was "one of the most prolific fundraisers among House members not holding a leadership role, while cultivating a reputation as a conscientious and moderate lawmaker.

[41][42] McSally was expected to run as the establishment candidate in the Republican primary, where her opponents included former state senator Kelli Ward and former Maricopa County Sheriff Joe Arpaio.

"[45] But in the lead-up to announcing her candidacy for Senate, McSally began to embrace Trump, running ads echoing his conservative immigration policy positions.

[46] Politico wrote: "Martha McSally wants to make one thing clear before she launches an Arizona Senate campaign: She's a big fan of President Donald Trump.

"[47] In an August 2018 candidate forum hosted by the Arizona Republic in advance of the Republican U.S. Senate primary, McSally and opponent Kelli Ward both said they were unconcerned with Trump's personal character, viewing it as a nonissue in the race.

[48] McSally won the August 28 Republican primary with 53 percent of the vote and faced Democratic nominee Kyrsten Sinema in the November general election.

[55] McSally ran to complete the term to which she had been appointed by Governor Doug Ducey, defeating skincare executive Daniel McCarthy in the Republican primary.

[82] A Democratic super PAC targeted McSally over her coronavirus response and comments she made in early March saying that "calling on people to stay home from work or to skip spring break trips is 'too much of a panicked reaction.

McSally initially did not take a position, calling it a "state issue," but she later announced that she opposed the law because she supports exceptions for rape and incest.

[117] In March 2020, McSally became a cosponsor of legislation to repeal the Davis-Bacon Act of 1931, which requires paying laborers and mechanics the local prevailing wages for public works projects.

[124] In October 2017, once construction was completed, she gave the keynote address at its dedication, calling it a "great example of member-driven co-ops, from the bottom up, figuring out ways to provide reliable power to the community, instead of top-down bureaucrats telling them what to do.

[127] During the House consideration of the National Defense Authorization Act for Fiscal Year 2016, McSally, along with John McCain, fought to increase military spending, particularly on the Tomahawk missile and other programs of Raytheon Co., one of Arizona's largest employers.

[133][134] In 2015, McSally said the air strikes taking place against ISIL were not effective but did not give an opinion on whether the U.S. should send ground troops into Iraq and Syria.

[135] In July 2018, McSally issued a statement touting Trump's actions to prevent "Russian aggression": she listed sanctions, the expulsion of diplomats, and working with NATO as some of them.

[136] In January 2019, McSally was one of 11 Republican senators to vote to advance legislation intended to prevent President Trump from lifting sanctions against three Russian companies.

[137] In October 2019, McSally was one of six senators to sign a bipartisan letter to Trump calling on him to "urge Turkey to end their offensive and find a way to a peaceful resolution while supporting our Kurdish partners to ensure regional stability" and arguing that to leave Syria without installing protections for American allies would endanger both them and the US.

[140] In 2019, the Arizona Mirror wrote that McSally "has suggested some willingness to consider gun control measures, an apparent shift from her previous stance on the topic."

McSally said she was considering "specific legislative efforts to prevent gun violence, like red flag laws, assault weapons bans and stricter background checks".

"[149] According to the Associated Press, on the date of the vote McSally stood up at a meeting of the House Republican Conference and told her colleagues to get this "fucking thing" done.

[161] Instead, she expressed support for a more conservative bill that would cut legal immigration, dramatically increase spending on border security, and provide indefinite stay for DREAMers but not give them a path to citizenship.

[168] In response to the Keep Families Together Act, which would have blocked the policy, she falsely claimed that the bill, backed by her Senate opponent Kyrsten Sinema, was "essentially encouraging child trafficking".

[170] McSally opposes net neutrality and signed a letter to FCC Chairman Ajit Pai in December 2017 urging him to repeal the Federal Communications Commission’s Open Internet Order.

[176] In May 2016, McSally voted for a bill that would have dismantled the Obama administration's executive action that made it illegal for government contractors to discriminate against people based on sexual orientation.