Friedrich Merz, the leader of Germany’s Christian Democrats and its leader-in-waiting for the last 10 weeks, failed in his first parliamentary vote to become chancellor on Tuesday morning.

The setback was likely temporary: Mr. Merz’s party, its sister party, the Christian Social Union, and their coalition partner, the center-left Social Democrats, still have enough votes to elect a chancellor and form a government. Mr. Merz will now need to pressure the six holdout voters from his coalition to support him on a second ballot.

But it was a stumble without German precedent. Since the founding of modern Germany, no candidate for chancellor has ever failed the first round of voting.

It was unclear when a second vote will be held.