Second, from AviationPros.com:
In 1964 Roy Shwery began one of the country's first commuter airlines called Midstate Airlines out of Marshfield, Wisconsin. The airline originally operated a fleet of Beechcraft Model 18 aircraft, and later, four Beech 99's.
By the early 1970's Midstate also was serving Hayward and Ashland, Wisconsin from the Central Wisconsin Airport and Ashland from the Minneapolis - St. Paul International Airport. One of its most fondly remembered features was the 6:00 PM "Champagne Flight" out of O'Hare, destined for Ashland via Milwaukee, the CWA, and Hayward. Shortly after takeoff from Milwaukee, the passengers were invited to open a cooler put onboard in Milwaukee and prepared by Midstate's President's wife.
Typically, in the cooler were a few soft drinks, beers, Wisconsin cheese, Pringle's Newfangled Potato Chips, plastic cups and one or two bottles of champagne. Somehow, this ice-breaker generated informality and good feeling for nearly everyone on board. In 1977 Midstate switched to 19-passenger Swearingen Metroliners.
In its heyday, Midstate operated a fleet of 19 Metroliners and added six Fokker F-27 50-passenger aircraft in 1984 (which required a flight attendant and a certificate modification under FAA part 121 rules), and flew to 15 cities in Wisconsin, Minnesota, Iowa, Missouri, Indiana, Michigan, Ohio and Chicago O'Hare airport.