The opposition is well-known for their constant infighting. Just think of Chiam, Chee and the SDP CEC. No one really cares who is right and wrong. All they see is the opposition in civil war, even while they are fighting over imaginary powers and their imaginary rule over Singapore. The people look at the PAP, a much larger organization several times over than all the opposition put together, and they see unity and discipline in the ranks. Most fence sitters will end up naturally voting for PAP.