Updated

One of Germany's most prominent left-wing politicians is leading a new movement launched Tuesday with the aim of reviving the fortunes of the country's ailing left by attracting like-minded people across party lines.

Lawmaker Sahra Wagenknecht, whose Left Party grew out of the former East Germany's communist party, and two members of the Greens and the Social Democrats said more than 100,000 people have pledged online to support their initiative.

"We are witnessing a crisis of democracy in Germany," and the new group — called Stand Up ("Aufstehen" in German) — —wants to reach citizens who "no longer feel represented" by mainstream politics, Wagenknecht, the Left Party's parliamentary leader, told reporters in Berlin.

The Left Party and the Social Democrats have lost disaffected voters to the far-right Alternative for Germany, or AfD. The nationalist party won enough votes to enter national parliament for the first time in September and continues to show well in polls, particularly in states that were part of East Germany.

The growing visibility of the far right in Germany was seen last week after two migrants were arrested in the killing of German man. The Aug. 26 slaying gave rise to street protests that brought together neo-Nazi groups, AfD supporters and Germans opposed to Chancellor Angela Merkel's welcoming immigration policies.

Ludger Vollmer, a founding member of the Greens, and Simone Lange, a Social Democrat who is mayor of Flensburg in northern Germany, are founding members with Wagenknecht of the Stand Up group.

Nationally, the center-left Social Democratic Party is a junior coalition partner to Merkel's center-right Christian Democrats, while both the Left Party and Greens are in opposition.

The three said Tuesday they neither want to create a new party nor break away from their own parties. Instead, they said Stand Up would pressure the political establishment to deal with the worries and concerns of average Germans, such as housing costs, bad schools, a nursing shortage and low salaries.

Other members of the country's three left-leaning parties have expressed skepticism.

Thuringia state Gov. Bodo Ramelow, a Left Party member, said "a movement needs to develop from the bottom" and not be initiated by party members.