Greek Socialist PASOK Party's leader Evangelos Venizelos

Greek Socialist PASOK Party's leader Evangelos Venizelos delivers a speech during a pre-election rally in Thessaloniki April 29, 2012. Crisis-hit Greece heads for an electoral cliffhanger on May 6 after two years of tough austerity that shook the country to its core, sweeping its dominant political parties in a torrent of anger. Greek socialist leader Evangelos Venizelos will seek to overturn stiff odds at next Sunday's national election, just over a month after helping to wipe out nearly a third of the country's huge debt.