Pat Hynes upsets Fritz Kaegi in Democratic primary for Cook County Assessor

Why it matters: The Cook County Assessor oversees property valuations that directly shape tax bills for millions of residents.

By the numbers: Hynes squeaked by Kaegi by the slimmest of margins, winning with 52% of the vote.

The intrigue: Hynes prevailed with support from the Cook County Democratic Party, led by President Toni Preckwinkle, which backed him over incumbent Kaegi.

Zoom in: Hynes won a hard-fought campaign that featured several negative attack ads.

• Hynes, whose uncle Tom Hynes ran the office from 1978 to 1997, blamed Kaegi for skyrocketing property tax bills, primarily on the South and West sides of the city.
• Hynes also worked for Kaegi as a field assessor.
• Kaegi, who positioned himself as a progressive reformer, argued Hynes would expand tax breaks for downtown commercial properties while shifting more of the burden onto homeowners.

The bottom line: Backed by the Democratic machine, Hynes is now poised to take over one of Cook County's most consequential offices.