2018Flipped from RepublicanFinal results
2018 election for U.S. Senate in Arizona
U.S. Senate · Arizona
Kyrsten Sinema (D) won with 49.9% of the vote, defeating Martha McSally (R) by 2.3 points, a seat Republicans won last time.
Kyrsten SinemaDemocrat · winner
49.9%1,191,100
Martha McSallyRepublican
47.5%1,135,200
Angela GreenGreen
2.4%57,442
2,387,543 votes
Source: MIT Election Data and Science LabUpdated Oct 1, 2026, 6:17 AM ET
The seat over time
D − R margin in this seat's races around 2018
Races before and after
Source: MIT Election Data and Science LabUpdated Oct 1, 2026, 6:17 AM ET
Money in this race
Each line compares the two campaigns on one scale.
Kyrsten SinemaMartha McSally
$22.6M
Raised by the campaign
$21.9M
$24.7M
Spent by the campaign
$21M
$171.5K
Cash on hand
$923.8K
Campaign money: FEC, through Dec 31, 2018.
Source: FEC campaign filingsUpdated Dec 31, 2018