Shares of Tesla had been on a tear since Donald J. Trump won the presidential election. Investors were betting that the carmaker would benefit from the more than $250 million that its chief executive, Elon Musk, spent to support the Trump campaign.
But an 8 percent decline in Tesla’s stock on Tuesday all but wiped out what was left of that rally. Investors who once thought that Mr. Trump could help clear regulatory hurdles for Tesla autonomous driving technology have grown concerned that Mr. Musk is spending too much time in Washington while Tesla sales plummet.
They also worry that Mr. Musk’s immersion in right-wing politics, including his endorsement of a far-right party in German elections on Sunday, are alienating significant numbers of buyers. In the United States, even some Republicans have become alarmed at Mr. Musk’s slash-and-burn cost cutting as head of the so-called Department of Government Efficiency.
The decline in the shares, which has pulled Tesla’s market value below $1 trillion, threatened Mr. Musk’s status as the richest person in the world because much of his wealth is in Tesla stock. And the declines will stir further unrest among investors and employees who are upset that Mr. Musk has not articulated a plan to halt steady erosion of market share in the United States, Europe and China.
The shares closed at $302.80 on Tuesday, the lowest since Nov. 7, two days after the election. That was down 37 percent from a peak of $479.86 at the close on Dec. 17.
The losses on Tuesday were at least partly a reaction to a catastrophic decline in Tesla’s European sales, which fell 50 percent in January from a year earlier, according to new-car registrations tallied by the European Automobile Manufacturers’ Association. Tesla sales fell in the region even as the overall market for electric vehicles surged 34 percent, according to a report by the association on Tuesday.
Tesla’s performance recently has shaken the faith of some investors who have long been optimistic about the company’s prospects. Gary Black, managing partner of the Future Fund, who has 488,000 followers on X, said on the social network Sunday that he had been “wrongly bullish” about Tesla “for four years now.”
Mr. Black noted that sales of the Cybertruck pickup, Tesla’s newest vehicle, have been disappointing and that the company has been forced to cut prices for its Model 3 sedan and Model Y sport utility vehicle to prop up sales, cutting deeply into profit.
But he said that his firm still owned Tesla shares and that it expected them to recover to $380 in six to 12 months.
