Personally, I am much more scared of the CDU (more so than of the CSU) and its "mainstream" agenda of the creeping Anglo-Saxonisation German economy - and of the fact that the SPD will replay the role of the Senate Democrats in the Iraq war here - than the ex-commies and 'idealists'. (BTW, while the PDS is full of old party members who more care about each other than social justice, it also absorbed younger leftist movements and reformists; and let's not forget that Gysi - who was always the face of the PDS who was popular even in the West - used to defend dissidents as a lawyer.)
In short: unlike the majority of German voters, I am more scared of the elitists than the populists.
I hope WASG/PDS can maintain the momentum and will do fine in the still far-away elections - but even that won't stop the CDU, only give voice to dissent that the SPD (and to a lesser part the Greens) won't give. *Lunatic*, n. One whose delusions are out of fashion.