Political leaders have shunned the Alternative for Germany. But on his social media platform X, Mr. Musk is pitching the party as mainstream.

The publicity was a potential boon for AfD, which has been frozen out of mainstream politics, in part, because its leaders have downplayed Nazi atrocities.

AfD is also focused on ending Germany's policy of atonement for World War Two crimes. Its leading candidate for the European Parliament election resigned from the party in May amid public outcry, after declaring that members of the SS,