The 49-year-old Love carded seven birdies in the round with three bogeys to be level with fellow Americans Martin Flores, Glen Day and Harris English, along with Australians Stuart Appleby and Nathan Green at the top of a crowded leaderboard.
Love upstaged his marquee group of defending champion Dustin Johnson (67) and world number six Brandt Snedeker (70).
Johnson was part of a logjam of 10 players just a shot off the lead in a tie for seventh including David Toms, Scott Stallings and Peter Hanson.
The Australian pair of Appleby and Green were surprise leaders given the two former winners have not had any impressive form of late.
In his 200th start on the PGA Tour, Green went bogey-free with four birdies.
The 2009 Canadian Open winner has just two top 10s since his lone win almost four years ago and plays out of the former champion category.
This time he took advantage of one of his rare starts on tour.
"The last few years my game has gone a little bit south," Green said.
"The game is changing a little bit. I was always a really good chipper and putter, and I lost that part of my game almost totally. I am sort of rebuilding that.
"To get around here without any bogeys is pretty good."
Appleby, a nine-time winner on tour, last won in 2010 at the Greenbrier Classic and he has just one top 10 since.
World number 10 Phil Mickelson failed to threaten the leaders with a round of 71 as he looks to get sharp for the U.S. Open next week.
Mickelson started well enough with a birdie on the 10th hole, his first, but found drama on a three-hole stretch soon after.
The four-time major champion bogeyed the 15th before producing a rare debacle at the par five 16th.
After making the greenside bunker in two Mickelson threw his sand shot way over the green after catching it thin and his return flop shot ended up back in the beach where he started.
Unable to get up and in from the trap again, he carded a double bogey seven.
Another bogey on the 17th had the five-time U.S. Open runner up in trouble. But showing plenty of fight he birdied the opening three holes on the front side of the course to get back to level par.
A late bogey on the ninth left him with his 71 and in a tie for 80th.
"My short game wasn't sharp today," Mickelson told reporters. "I made a mistake in some of my shot selections, trying to hit some of these shots off very tight lies. I tried a few shots and I struggled with them.
"I really feel like I'm striking the ball well and the score obviously isn't very good especially the way I feel I'm playing but this is the first competitive round I've had in a little while.
"I'm looking forward to tomorrow's round because I know ball-striking wise it's about as good as I've been striking it and I feel like there is a good round in me."
(Reporting by Ben Everill; Editing by Ian Ransom)