State Senator - District No. 13
July 21, 2026 · State Senate District 13; Arizona · State senate district · primary
How do we calculate vote impact?
Vote impact = representation (how much weight one vote carries here, the smaller the district's population, the higher the representation) + decisiveness (how likely this race is to be close, based on past results and number of candidates).
Representation: High · 66 out of 100
Smaller districts give each vote more weight, and this district is small for its type. About 237,864 people live here.
score = 100 × ln(largest population ÷ this district's) ÷ ln(largest ÷ smallest), rounded to 2 decimals = 100 × ln(275,769 ÷ 237,864) ÷ ln(275,769 ÷ 221,081) = 66.9, comparing state senate districts in AZ (grades: 66+ high, 33+ average, otherwise low)
Decisiveness: Unknown
No past results for this contest yet.
High representation + unknown decisiveness → High vote impact.
Some data is missing, so this rating is based on partial information and capped at "High".
State Senator is responsible for:
- Voting on state laws and the state budget
- Representing their district in the state senate
- Confirming certain governor appointments in many states
- Helping district residents deal with state agencies
Affected Areas: Environment and Public Health, Reduce Wealth Gap, Anti-Corruption, Government Efficiency, Healthcare Affordability, Government Spending Reduction, Public Safety and Crime Control, Housing Affordability, Social Programs and Welfare, Public Education Quality, Gun Control, Women's Reproductive Rights, Election Integrity, Personal Income Tax Reduction, Data Privacy, Civil Rights, Corporate Accountability, Public Infrastructure
Candidates
Julie Willoughby
Republican · declared
Julie Willoughby is a Republican Arizona state representative for Legislative District 13 and House Majority Whip. She is a registered nurse and healthcare leader whose career has included trauma emergency medicine. She holds a Bachelor of Science in Nursing from Arizona State University and was appointed to the House in May 2023 before winning election in 2024.
Records: Data Privacy 1 for, 1 against, Election Integrity 1 for, Environment and Public Health 2 for, Government Spending Reduction 1 against, Healthcare Affordability 1 for, Housing Affordability 1 for, Personal Income Tax Reduction 1 for, Public Education Quality 1 for, Public Safety and Crime Control 2 for
Kristie O'Brien
Democratic · declared
Kristie O'Brien is a Chandler lawyer and mediator running as a Democrat for Arizona State Senate District 13. She grew up in Chandler, graduated from Dobson High School and Trinity College, worked on Capitol Hill for both Republican and Democratic offices, and later worked at the International Criminal Court in The Hague.
Records: Anti-Corruption 1 for, Civil Rights 1 for, Environment and Public Health 1 for, Gun Control 1 for, Healthcare Affordability 1 for, Public Education Quality 1 for, Women's Reproductive Rights 1 for
Election sources
Source: azsos.gov
Source: azsos.gov