Republican Steve Hilton and Democrat Xavier Becerra lead the field as votes continue to be counted

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The key race for California governor remained deadlocked as vote counting continued across the US on Wednesday morning following primary elections to decide who would run in several critical districts in the US House and Senate in November, in a midterm year expected to favor Democrats.

In California, it was the Republican Steve Hilton, a former UK political operative and Fox News host, who had the most votes, with roughly half of the ballots counted for governor. For the Democrats it was Xavier Becerra, the former health secretary, who led the field after a tumultuous campaign. The California system is such that the two candidates who receive the most votes then face off in the general election, no matter which party they are from. Many Democrats in the state held on to their ballots until the last minute, so the early results were expected to favor Republicans.