Peter Senior found himself in good position to win his first event since joining the Champions Tour last year.
Senior shot a bogey-free 67 and John Huston birdied No. 18 for a 68 on Saturday that left them tied for the lead at 12 under after the second round of the 3M Championship.
Jay Haas, the co-leader after the opening round, shot a 69 and was one shot back.
"It'd be nice to win one. I've had a couple of opportunities and never really went ahead with it," Senior said.
Last week at the U.S. Senior Open, he was tied for third entering the final round, but shot a 71 -- the highest score of his four rounds -- and finished sixth, the second time he finished in that place in five weeks. He also lost in a playoff at the Regions Tradition in May.
Senior birdied three of the four par 3s Saturday. He hit 27 of 28 fairways in the first two rounds, and 33 of 36 greens in regulation.
"I really didn't have to struggle for any par, which is always nice to do," he said. "I had plenty of opportunities but the greens were a little slower today after the storm. ... It's nice to be in the position I'm in."
Play was delayed 1 hour, 56 minutes due to rain and lightning when the leaders began their back nine at TPC Twin Cities.
Early in the day, the course played much like it did Friday when 53 of 80 players broke par by firing right at the flags. However, the wind began to pick up as the final groups began their rounds around noon, quickly reducing the number of birdies that were being posted. Following the stoppage, the wind was not a factor and scores slowly began to drop again. Forty-five players broke par.
Mark Calcavecchia (68), who finished second in last year's event, and Minnesota native Tom Lehman (69) were two shots behind.
Tommy Armour III (67), Mark O'Meara (68), Kenny Perry (70), Nick Price (68) and Hal Sutton (69) trailed by four.
Huston birdied the first two holes to get to 10 under, and increased that lead with a 25-foot birdie putt on the tough ninth hole. Haas also birdied No. 9 to stay within two strokes of the lead.
After a birdie at No. 11, Huston hit his tee shot on No. 12 into a water hazard, leading to a bogey. Haas and Lehman birdied the hole to get within one shot.
"I was just kind of trying to hold it together the rest of the way," Huston said. "I hung in there. I made a good par on 16 after a really bad tee shot, and I was fortunate enough to make birdie on the last one."
Senior birdied Nos. 13, 15 and 17.
Haas missed a short putt on No. 18 that would have him tied for the lead.
"Jay had a lot of opportunities from 10, 15 feet and missed a 3- or 4-footer at the last hole," Senior said. "He could have really had a real good score today."
Calcavecchia had birdies on Nos. 14 and 15 to get within a shot. A bad approach shot on 18 -- statistically the easiest hole on the course -- cost him a birdie opportunity. He also missed four putts from within 4 feet during his round, saying he turned a potential 63 into a 68.
"If I play great tomorrow and don't miss any putts inside 5 feet, 6 feet, I'll shoot a good score. I'm hitting it great. It's just frustrating," he said.
Lehman, a three-time winner this year and the season points leader, made three bogeys and said he couldn't get any momentum going but still has a chance at winning.
"There are a lot of guys within four, five shots of the lead and somebody's going to go low, and if the weather's real nice, somebody's going to go real low," Lehman said. "You hope you're the one that does."