Members of German Chancellor Angela Merkel's Christian Democratic Union (CDU) are having as much fun with their regional conferences as a child with a new toy. At them, Merkel's three most probable successors are making the case for why they should lead the party. Although the primary format is well-established in the USA, it is utterly new to Germany's conservative party.

With just over a week until the final vote at the party's annual conference in Hamburg, the race is in its final stretch. Buses full of regional associations are arriving at such conferences in droves to hear what the candidates have to say. Today, after feasting on bockwurst and posing for group photos, 4,000 party members head into the trade fair exhibition halls of the North Rhine-Westphalian (NRW) capital, Düsseldorf. There they get the chance to see Annegret Kramp-Karrenbauer, Friedrich Merz and Jens Spahn up close, in what is the sixth of eight such regional conferences.

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Attacking the Greens, distancing the SPD

"We have to be ready to lead controversial debates," Merkel's former rival Merz tells the capacity crowd. The response is thundering applause from a party base that seems to be fed up with consensus. The former parliamentary group leader is using his home field advantage. He emphasizes his "rural roots" in the nearby Sauerland region and vehemently attacks North Rhine-Westphalian Greens for their support of coal protesters in the Hambach Forest. "The Greens need to clear up their relationship to this state's monopoly on the use of force," says Merz, once again garnering thunderous applause. He bemoans the fact that "the clarity of our positions has suffered" and calls for a starker delineation of CDU policies from those of its junior coalition partners in the German government, the Social Democrats (SPD).

This evening's host is the state CDU — the party's largest state association. North Rhine-Westphalia is also the home of two of the three top candidates: Merz and Spahn. Almost one-third of the delegates at the Hamburg vote on December 7, will travel there from NRW. The candidate who does best here will have taken a big step toward victory in Hamburg — and toward CDU party leadership.

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Self-confidence vs. conciliation

Merz was able to garner much more applause here than either of his competitors. Spahn — the 38-year-old politician currently serving as health minister in Merkel's cabinet — often muddled his words. Close Merkel ally Kramp-Karrenbauer appeared reserved. Merz, however, exuded self-confidence, stating in an interview before the conference: "Not only do I intend to win, I fully expect to be elected CDU chairman."

Nevertheless, polls among the CDU and the general population currently show him lagging behind Kramp-Karrenbauer. Though she is currently party secretary and a well-known name in politics, she cut a much quieter and reserved figure than either of her counterparts in Düsseldorf.

Whereas Merz wants controversial debates, Kramp-Karrenbauer made the case for "constructive debate." She also gave the base hope: "We are looking to capture 40 percent of the vote in Germany and its state associations. And that is the bar by which we will be measured." Currently, the CDU is hovering around 27 percent favorability among voters — its lowest numbers in decades.

Enjoying the competition

Frank Sarfeld likes what Kramp-Karrenbauer has to say. A communications advisor from Düsseldorf, he has been a member of the CDU for 30 years. "Annegret Kramp-Karrenbauer represents the majority of the CDU," he says, adding: "The CDU must once again be led with emotion and passion and I only see that with her." Sarfeld is also pleased with the party's "brilliant debate culture. That is something we have over the other parties." Mats Müllenbauer, a 26-year-old engineering student from Aachen, feels that Friedrich Merz carried the evening. Müllenbauer says he doesn't agree with all of Merz's positions but thinks he was more authentic than his competitors, before he turns to listen to the candidate's closing remarks.

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Other German parties have much more experience with inner-party competition than the CDU, yet none of them seem enjoy the spectacle as much as the CDU is right now. The Christian Democrats will have two more opportunities to whoop it up before heading to Hamburg to get behind the party's new chairperson.