Delfino led the Bucks with 24 points and eight assists, and Brandon Jennings contributed 18 points and 13 assists.
Milwaukee shot 57.6 percent from the floor to Minnesota's 38.4 percent.
"We executed pretty well, we moved the ball, found the open man and the shots went down," said Bucks Coach Scott Skiles. "We played a very unselfish game."
The Bucks rode a 14-0 run in the first quarter and a 42 fourth-quarter points to their second win in their last three games.
Jonny Flynn led the Timberwolves with 20 points and five assists. Corey Brewer scored 18 points. The loss was Minnesota's seventh in their last eight games.