The Rise of Sunshine Pop

For every sunny pop hit of the mid-1960s and early '70s that you know, there were dozens of others with similarly upbeat feels that never made it high up on the charts. For instance, you certainly know the Mamas and the Papas' California Dreamin', Gary Puckett and the Union Gap's Over You, the Fifth Dimension's California Soul, the Young Rascals' Groovi…