Will the PDI absorb voters from the FPS, given the ideological overlapping that will exist?The FPS is the Federación de Partidos Socialistas, one of the two main socialist parties, containing the PS, CSC, CSM, PSPV, EIA, PSA and others. In the 1970s, they combined social democracy with monarchism and federalism. The PS comes from the old PSI. I won't say more.
The PDI is however the successor of the PCE once it goes from Eurocommunism to social democracy.