Early this year, the consensus was that they headed for a crushing defeat. Then overconfident opposition got greedy. They fought among themselves for the expected spoils. They were hijacked by small number of very militant leftwing elements. These people started to feel that they no longer needed to keep their head down and showed their colors. Closet commies were coming out openly to be in the driver seat of power. That scared many of those disaffected by the corruption and blatant cronyism in current government. Watching them showing up in numbers in the heart of Seoul, openly and brazenly taunting those who are dejected by their behavior, made people closing rank against them. They thought they were finally going mainstream and spook others to follow their lead. Instead they met huge backlash.
I wonder what will happened to ruling camp which could become overconfident themselves. For now, ruling party appears to be heading for easy victory, but it is not a done deal. Park Geun-hye could shoot herself in the foot with ill-advised moves.