Kelly was joined at minus-2 by Carlos Franco (70), Jesper Parnevik (72), Jerry Kelly (66) and Bob Heintz (70).
World No. 2 and defending champion Vijay Singh moved back into contention with a 4-under 66. He is tied for eighth at minus-1 with six other players.
Calcavecchia stumbled out of the gate with a bogey at the first. He got that stroke back with a birdie on the par-3 third at Shaughnessy Golf & Country Club after sticking a 5-iron within 2 feet.
The 45-year-old parred his next three holes before catching fire. Calcavecchia birdied the par-5 seventh from 20 feet out to move to minus-6. He made it two straight as his 6-foot birdie try on eight fell into the cup.
Calcavecchia dropped in a hard-breaking, 20-foot birdie attempt at the ninth to make it three straight and get to minus-8. The 11-time winner on the PGA Tour parred the first six holes of the back nine.
He struggled to a bogey on the par-4 16th to fall back to 7 under after his second shot flew the green and he was unable to get up and down for par.
Calcavecchia atoned for that error with a 6-foot birdie on the par-4 closing hole to move five clear of the field.
'Today I felt good. Actually, starting out I almost felt too relaxed,' said Calcavecchia. 'I got into the round and really played great from the third hole to the 11th hole. I played okay on the back, but birdied the last hole which was nice. Two real good ones there.'
Glover started on the back nine with seven consecutive pars. He birdied 17 to get to minus-6, but bogeyed 18. He fell down to minus-2 with bogeys on one, three and five.
The 25-year-old got one of those strokes back with a birdie on the par-5 seventh. He parred his final two holes to remain there.
Singh started his round with a bogey on No. 1. He bounced back with birdies at three and four, but stumbled to another bogey on five. He birdied the seventh to get to plus-2.
The world No. 2 dropped in back-to-back birdies from the 10th to climb to even par. Singh carded his final birdie on 14 before parring his final four holes.
Singh was joined at 1-under-par 139 by Matt Kuchar (67), Ryan Moore (70), Trevor Immelman (68), Ted Purdy (72), Arjun Atwal (67) and Brent Geiberger (71).
The cut line fell at 4-over-par 144 with 73 players moving on to the weekend. Among those who missed the cut were Jason Gore (145), Canadian Mike Weir (146) and former PGA champion Rich Beem (147).