Split-ticket voting is when you vote for different political parties down the ticket — like voting for a Republican Senator at the same time as voting for a Democratic Representative.
As a FiveThirtyEight article shows, unusual levels of split-ticket voting are when it creates a difference in vote shares of more than about 5%.
In the case of Democrat votes for the US House of Representives in Arizona, the votes for Hobbs for Governor were over 10% higher than the votes for the U.S. Representatives of the same party, indicating an anomaly:
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