The Democrats’ leading candidate for California governor tried to end an interview after being asked how she would win over Donald Trump supporters.

Katie Porter, whom polls show leading the pack to replace Gavin Newsom in next year’s election, accused a CBS reporter of being “unnecessarily argumentative” in a fractious interview.

Rival Democrats also running to clinch the party’s nomination for governor accused her of dismissing voters and being unable to answer “simple questions”.

Ms Porter was pressed by correspondent Julie Watts after claiming she would not need to win over Donald Trump’s supporters to become governor.

The former congresswoman frowned, turned to the camera and laughed openly, before asking in apparent incredulity: “How would I need them in order to win, ma’am?”

Porter appears to contradict herself

Ms Porter went on to claim she would win every vote of the 60 per cent of Californians who did not vote for the US president in last year’s election to beat a Republican candidate in the gubernatorial election.

When asked how she could do so in a primary contest against other Democrats, she replied: “I don’t intend that to be the case.”

Ms Porter then appeared to contradict herself, saying she had won Republican votes in the past when she represented a swing district in Orange County, which has a strong conservative streak.

“I feel like this is unnecessarily argumentative,” she then said, before placing her hands in front of her as if trying to keep Ms Watts at bay. “What is your question?”