After drawing a spillover crowd to the M&I Classic Rock Stage at last year’s Summerfest, the perennially popular funk ensemble Earth, Wind and Fire traded up to the Marcus Amphitheater this year. Because of their strong disco ties, the group never carried the same prestige as peers like Sly and the Family Stone or Funkadelic, but at their best they were every bit as visionary as those greats. They simply preferred to downplay politics and oddness in favor of an inclusive, happy-go-lucky spirit that drove hits like “Sing a Song,” “Shining Star” and “September,” the latter of which Danny Gokey memorably covered on “American Idol.”
Earth, Wind and Fire share tonight’s bill with the similarly large and similarly veteran jazz-rock band Chicago, which has been touring for four decades without ever taking a hiatus. Many of its original members remain, including its principle songwriters—the major exception is singer Peter Cetera, who left for a short-sighted solo career back in 1985.