The leading candidate, Friedrich Merz, a conservative who has adopted many of the AfD’s hard-line positions on immigration, used his closing statement of the debate to promise his voters that he would never allow the AfD into his government. Under him, he said, the firewall would hold.

As Germany heads to parliamentary polls on Sunday (February 23), the spotlight will be firmly placed on the divisive far-right party, the Alternative for Germany (AfD) and its leader, Alice Weidel.

On Sunday, the country’s residents will vote in a pivotal election in which Ms Weidel's party, Alternative for Germany (AfD), is tipped to come in second. A snap election was called at the end of last year by current Chancellor Olaf Scholz, of the Social Democratic Party (SPD), when his coalition Government fell apart.

Germans will head to the polls Sunday looking for leadership at a deeply uncertain time, but all eyes will be trained on a party likely to finish a distant second.

On a wet evening in Suhl, in the former East Germany, a smattering of youthful faces were among hundreds lining up to hear from an unlikely idol - Björn Höcke, one of the most controversial figures in the far-right Alternative for Germany (AfD) party.