Answer: groundswell

AnswerCrossword Clue
GROUNDSWELLSurge of support
GROUNDSWELLSurge of popular support
GROUNDSWELLPelagic undulation.
GROUNDSWELLBases soundly
GROUNDSWELLSurge, as of political action
groundswellA large or extensive swell in the sea
groundswella broad, deep undulation of the ocean caused by a distant gale or earthquake
groundswellA buildup of opinion or feeling in a large section of the population