Kansas has unexpectedly become a key battleground state this election cycle. The latest sign: The widely trusted Cook Political Report shifted the race from “Leans Republican” to “Toss Up” on Monday.

“Like a Rubik’s Cube, not much about this race makes a lot of sense to most observers,” the website writes. “So we are going to stop trying to make sense of the nonsensical and accept that everything about this race is so unpredictable and unconventional that the only rating that makes any sense is Toss Up.”

The race had been considered a relatively safe seat for Republicans, until Democratic nominee Chad Taylor filed to withdraw from the race earlier this month. After the state’s supreme court ruled against Kansas’s secretary of state and allowed Taylor to drop out, Democratic voters have unified behind independent candidate Greg Orman, putting Roberts into a close race.

In its description for the ratings change, Cook notes that Orman’s vagueness on the campaign trail on the issues and what party he would caucus with raises questions about whether his popularity will last.

Kansas joins Georgia and Kentucky as the three Republican-held Senate seats currently rated “Toss Up,” compared with Democrats’ seven seats in the same category.