BERLIN (AP) — German Chancellor Angela Merkel and her center-left rival, Martin Schulz, are set to hold their only televised debate Sunday, three weeks before the country's general election.

Both candidates have run a lackluster campaign so far, prompting yawns from political commentators. The latest edition of respected weekly Der Spiegel called on Merkel and Schulz to "wake up!"

Some 20 million Germans — almost a third of the electorate in this country of 80 million — are predicted to tune in to the 90-minute debate to be broadcast simultaneously by four large TV stations from 8.15 p.m. (1815 GMT).

Merkel's Christian Democrats lead in recent opinion polls, with the Social Democrats coming second.

The parties are currently in a coalition at the national level.

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