The crowd reaction to the performance by the reunited Replacements at the Boston Calling music festival was nothing short of ecstatic. The Minneapolis band led by Paul Westerberg hadn’t played here in more than 20 years, and fans were overjoyed. Their zeal did not go unnoticed. At the band’s homecoming show the other night at Midway Stadium in St. Paul, Minn., Westerberg, bassist Tommy Stinson, and replacement players Josh Freese on drums and Boston’s own Dave Minehan on guitar delivered a stellar 31-song set. But when it came time to play “Androgynous,” a song whose lyrics Westerberg often forgets, the crowd in St. Paul couldn’t fill in the blanks, at least not enthusiastically enough. “Boston was better,” Westerberg teased the crowd.