TOPEKA, Kan. (AP) — A contentious Kansas governor's race has become a referendum on how a Republican experiment in slashing income taxes went awry, what lessons arose from the budget misery that followed and whether the state needs a do-over.

Democratic nominee Laura Kelly, a veteran state senator, supported a successful effort last year to repeal most of the tax cuts and makes it a cornerstone of her campaign. She argues that Republican nominee Kris Kobach not only wants to repeat ex-GOP Gov. Sam Brownback's fiscal experiment but to top it.

"We all know that Kansas has gone through a world of...