Bavarian Elections Deal Blow to Merkel Coalition

State Vote Signals Chancellor’s Strength But Clouds Outlook for Junior Partner Ahead of National Polls.

A week before German Chancellor Angela Merkel is expected to come out on top in national elections, the stinging defeat of her junior coalition partner in Bavaria cast into doubt her chances of renewing her center-right government.

In a sign of strength for Ms. Merkel, the Christian Social Union won Bavarian state elections in a landslide with 49% of the vote, according to early returns. The strong result for the Bavaria-based CSU, a sister party of the chancellor’s Christian Democratic Union, reflected the broad support for Ms. Merkel throughout the country.

But the market-oriented Free Democratic Party, now the junior coalition partner alongside the CSU in Bavaria—as well as Ms. Merkel’s Christian Democrats in the federal government—was expected to receive just 3%, on the low end of what recent polls had predicted.

The result means that the FDP will lose its seats in the Bavarian Parliament, allowing the CSU to regain its role as the sole party in the state government.

On the national level, that doesn’t bode well for the future of Ms. Merkel’s current coalition, even though polls suggest voters will hand her a third four-year term when they head to the polls this coming Sunday.

Ms. Merkel’s Christian Democrats aren’t as popular across Germany as their sister party, the CSU, is in conservative and wealthy Bavaria and will need to build a coalition to stay in power in Berlin. Ms. Merkel has said she’d like to continue her center-right coalition with the FDP.

If the FDP fails, Ms. Merkel will likely have to team up with the main opposition party, the center-left Social Democrats, to keep her chancellorship.

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