|Muharrem Ince: A fresh new face in Turkish Politics|
The CHP plans to ally for the first time with right-wing parties, in the hope of beating Mr Erdogan.
Mr Erdogan's conservative AK Party has a majority in parliament.
He called the snap election to cement his position with enhanced powers. Parliamentary elections will be held on the same day, 24 June.
Secularists are fundamentally opposed to the AK Party's agenda, seeing it as creeping Islamisation of the state.
Read More: Turkey opposition names rival to Erdogan for June election - BBC News