Can I obtain Portuguese citizenship if my great-grandmother was a Portuguese Jew?

Hello, on my paternal side of the family my great-grandmother (mother of my fathers mother) was a Sephardic Jew (from Portugal.) However, my grandmother and my father (as well as his siblings) never obtained Portuguese citizenship. I know that the Spanish government offers a reduced time for someone to obtain citizenship if they are of Spanish Sephardic ancestry, however I was wondering if the Portuguese government offers anything similar? The main problem I think is that my great-grandmother and grandmother have deceased; my father and his siblings however are still alive. I can speak some Portuguese but nowhere near 100% fluency, I can however speak fluent Spanish, as my family is all from Nicaragua (where my the Portuguese Jewish grandmother emigrated to as well.) Would it be easier for me if I applied for Spanish citizenship instead? I am an American citizen and my desire is to obtain EU citizenship so I can move to Europe for cheaper graduate school. Thank you for your help, I understand if this is a little complicated.