[8][9] In 2020, she narrowly ousted incumbent state Senator Heather Carter, defeating her in a Republican primary challenge from the right following a heated race.

[12][13] The proposed repeal would end a requirement that parents exempting children from vaccines acknowledge the risk of serious illness and death from infectious disease.

[6][17] In 2020, Barto was one of 13 Arizona Republican state legislators who supported Donald Trump's failed attempt to overturn his loss in the 2020 presidential election.

† Won nomination for general election '2008: Barto, Republican Representative Barnes, Democratic nominee Jeanne Lunn, and Libertarian candidate Jim Iannuzo were unopposed for their September 2, 2008 primaries,[22] setting up a rematch; in the four-way November 4, 2008 General election, Barto took the first seat with 46,854 votes and Representative Barnes took the second seat ahead of Democratic nominee Jeanne Lunn and Libertarian candidate Jim Iannuzo.

[23] 2010: When Republican Senator Jim Waring ran for Phoenix City Council and left the Senate District 7 seat open, Barto and Representative Barnes both ran in the four-way August 24, 2010 Republican Primary, where Barto placed first with 10,475 votes (46.2%);[24] in the November 2, 2010 General election, winning with 41,849 votes (67.2%) against Democratic nominee Eric Shelley.

15: Barto and John Allen ran unopposed in the primary,[32] then both defeated the Democratic candidates, Julie Gunnigle and Jennifer Samuels, in the general election.