De Jonge followed his opening 62 with a 66 to match Blixt at 14-under 128 after two rounds in perfect conditions in the Fall Series opener.
"I think it's a lot of things that makes me play well this week," said Blixt, from Sweden. "I got my family in town, my brother and my sister, a couple friends from overseas, which makes it really relaxed. We're renting a house together and just having a good time. I don't think about golf at all coming off the golf course. Just hang out with them. It's easy to think about something else when you're in Las Vegas, right?"
Blixt is winless on the PGA Tour.
"I've been working a lot on my ball striking the last few weeks when I've been off," Blixt said. "It's not really there yet, but I got a hot putter and it's been helping me out a lot the last two days."
Blixt birdied Nos. 15 and 16, made a double bogey on the par-3 17th, and finished with a birdie on 18. He also had an eagle on the par-4 seventh hole.
"First of all, I don't know why they always put water on 17, on the par 3s," Blixt said. "Every single week we play on par 3s. ... It's a great hole, but if I miss it's left, so that's why I don't really appreciate it. But I just got a little fast and that's why I missed. Tried to hit a little soft 6-iron in there."
De Jonge, from Zimbabwe, also is seeking his first PGA Tour victory.
"We got a long way to go, obviously," de Jonge said. "I've played nicely for the first rounds, but to start thinking about winning right now would be jumping ahead a little bit.
"I've driven the ball well for the first two rounds. With as receptive as the greens are here, you're going to have a lot of chances when (you drive well). That's been the key. I've been able to set myself up to score well from the fairways."
Ryan Moore, the Las Vegas resident and former UNLV player who matched the TPC Summerlin record Thursday with a 61, was a stroke back after a 68.
"It was a good, solid round," Moore said. "I definitely would have liked to have seen a few more of those putts drop. But I hit good putts all day. They were just burning the edges, lipping out. All in all, I like my position going into the weekend."
John Daly was 10 under after a 63, his lowest score of the year. At 132nd on the money list, the two-time major champion is trying to move into the top 125 to secure full playing privileges for next season.
Daly had eight birdies, an eagle and two bogeys to match Summerhays for the best round of the day.
"Today, I hit the ball really well and I putted good the last two days, which is good for me," Daly said. "The greens are rolling really good, so it gives you an opportunity. If you hit it think decent, you can make some putts. ... But on any tour, any more, it's just putting. If you make some putts you can play really well. This course gives you a lot more opportunities than most courses."
Watney also lives in the area.
"It's fun. It's nice to play well at home," Watney said. "I got a lot of friends and family out, so I'm looking forward to trying to put together a nice weekend."
Singh had five birdies, an eagle and a double bogey on his final hole, the 444-yard, par-4 18th.
"I putted better today," Singh said. "I made some putts and had some good up and downs, and I made a bomb on No. 13 for eagle, so it kind of helps."
Defending champion Kevin Na was 8 under after a 66.
"I feel like I left a few out there, but on this course it's easy to do," he said.
Casey Martin missed the cut with rounds of 71 and 74. The Oregon coach, playing on a sponsor exemption, is allowed to use a cart in competition because of a rare circulatory disorder in his right leg.