CROMWELL, June 21, 2014 (AFP) - Langley, a 25-year-old seeking his first victory on the US Tour, had an 11-under par total of 129 after two rounds on the TPC River Highlands Course.
He was one stroke in front of South Korean K.J. Choi and Americans Michael Putnam and Harris English.
Putnam's 63 was the best round of the day, while English carded a 64 and Choi a 65.
"I just had really good tempo," Langley said. "The name of the game out here is putting. I putted quite well. I feel confident on the greens. My speed is pretty well dialed in."
First-round leader Brendan Steele was in a group on 131 after a second-round 69. He was joined by fellow Americans Ryan Moore (68), Eric Axley (67) and Jamie Lovemark (63).
Dustin Johnson was alone in ninth place after his second straight 66 for 132.
Through the first two rounds, Johnson has missed just six greens in regulation and made a dozen birdies.
"I'm hitting the ball well, I'm getting good looks at the hole, making some putts," Johnson said.
Langley, in his second season on the PGA Tour, is trying to become the fifth straight player to make the Travelers Championship his first tour win.
On Friday, he hit 13 of 14 fairways in regulation and 16 of 18 greens. His eight birdies offset a bogey and a double-bogey.
Langley teed off on 10 and birdied 11 and 12. He birdied 14 and 16 from within 10 feet and picked up another stroke with a birdie at one.
After a three-putt double-bogey at the second, he responded with a birdie at the next hole and sandwiched a bogey at seven between birdies at six and eight.
"My iron play has been really solid. I'm giving myself a lot of short putts for birdie," Langley said. "I struck the ball pretty well, kept the ball in play and putted pretty well."
Putnam opened his round with a bogey at 10, but didn't drop another shot in his seven-under effort that included eight birdies.
English countered his lone bogey with seven birdies while Choi had six birdies and a bogey for his share of second place.
Leading second-round scores on Friday at the $6.2 million US PGA Tour Travelers Championship on Friday (USA unless noted, par-70):
129 - Scott Langley 64-65
130 - Michael Putnam 67-63, K.J. Choi (KOR) 65-65, Harris English 66-64
131 - Ryan Moore 63-68, Eric Axley 64-67, Brendan Steele 62-69, Jamie Lovemark 68-63
132 - Dustin Johnson 66-66
133 - Matt Kuchar 66-67, Aaron Baddeley (AUS) 67-66, Bud Cauley 63-70
134 - Chad Campbell 64-70, Jeff Maggert 64-70, Brandt Snedeker 65-69, Sergio Garcia (ESP) 65-69, Johnson Wagner 68-66, Chris Stroud 67-67, Tim Wilkinson (NZL) 66-68
135 - Bae Sang-Moon (KOR) 67-68, Brian Harman 68-67, Patrick Rodgers 66-69, Heath Slocum 66-69, Brice Garnett 67-68, Charley Hoffman 67-68, Carl Pettersson (SWE) 68-67, Keegan Bradley 66-69