Yes, SUFFRAGE is a Scrabble word!

Letter values in Scrabble US: S 1, U 1, F 4, F 4, R 1, A 1, G 2, E 1.

Is it a valid word?

SUFFRAGE is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a legal right guaranteed by the 15th amendment to the US Constitution; guaranteed to women by the 19th amendment

Also: right to vote.