Musk tested the boundaries of foreign election interference, hosting AfD co-leader Alice Weidel for a livestream interview on X.

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.