When Anne Marie Squeo received her fiery red Tesla sports utility vehicle in 2020, the 55-year-old marketing and communications professional felt like she had joined a special “club” of people who were doing something to help the environment, while still driving with style.

But last year, as Tesla boss Elon Musk shared right-wing conspiracy theories on Twitter, posted a picture of guns by his bedside, and proposed terms to resolve the war in Ukraine that were adamantly rejected by many of the country’s top leaders, Anne Marie’s satisfaction gave way to shame.

“It’s been very depressing, and sometimes embarrassing to be driving this car around,” says Anne Marie, a former journalist who lives in Connecticut and wrote an article about her discomfort. “I wondered if people were making a judgement about me that I wasn’t looking for.”

Once hailed as the secret to Tesla’s success, Elon Musk now appears to be one of its biggest problems, as his steady stream of politically charged social media posts alienates key parts of Tesla’s customer base, just as increased competition starts to eat away at the firm’s dominance of the electric car market.

The value of Tesla shares plunged by roughly two-thirds last year – the biggest decline since the company went public in 2010 – reflecting the worries, as well as concerns about disruptions to production and the effect of high borrowing costs and a weaker economy on demand.

In December, major investors – many of them long-time allies of Mr Musk – went public with their alarm, accusing him of abandoning Tesla after his $44bn (£36.4bn) takeover of Twitter in October and damaging the car company’s brand.

The fact that Mr Musk sold roughly $20bn worth of Tesla shares last year – sales that weighed on the stock and were prompted at least in part by the Twitter purchase – did not help.

“It’s cost everybody a tonne of money. Certainly it didn’t protect Tesla shareholders,” says investor Ross Gerber, who is now seeking a seat on Tesla’s board of directors and calling for changes, including starting to spend money on advertising, which Tesla has long prided itself on being able to do without.

Mr Gerber, the head of Gerber Kawasaki Wealth and Investment Management and a self-described friend of Mr Musk, says