Story highlights German Chancellor Angela Merkel is facing the most important vote of her life

Merkel gains political capital within her party before next year's federal election

Atika Shubert is a CNN senior international correspondent based in Berlin.

Berlin (CNN) German Chancellor Angela Merkel is not one for rabble-rousing. In 11 years as the leader of Germany, her speeches are usually sobering analyses of thorny political and economic dilemmas, using only her signature diamond-shaped hand gesture to punctuate her points.

But on Tuesday night, "Mutti" or "Mom," as she is affectionately called, made an impassioned plea to her party: "I have also asked you for a lot," she told the more than 1,000 members of her Christian Democratic Union gathered, "because the times have asked us for a lot. I know that very well. And I cannot promise that the demands in the future will be any less because we have to do what the times demand from us."

Merkel is facing tremendous pressure from voters -- as well as from her own party -- for allowing more than 890,000 asylum seekers into the country last year.

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Initially, Germans opened their doors. Crowds came to train stations to applaud arriving asylum seekers, greeting them with flowers and chocolate. There is even a special word for it: "willkommenskultur."

But the numbers began to strain social services. Local councils complained there wasn't enough space to house everyone. Last year, one mayor took CNN for a tour of facilities , where refugees were forced to sleep on mattresses in the hallways of the official's office.