Lee opened with a four-under-par 66 to be sitting in a six-way tie for fifth, two shots off the pace at Pelican Golf Club in Belleair.
Australia's dual major winner and one-time world No.2 is languishing, uncharacteristically, in 56th spot in the season-long point standings.
Only the top 60 will qualify for next week's Tour Championship, leaving Lee needing a strong finish at the penultimate $US3.5 million ($A5.4 m) event.
Steph Kyriacou (60th) and Hira Naveed (72nd) also need to play well to extend their LPGA seasons by an additional week, but haven't made the best of starts.
Naveed opened with a two-over 72 and Kyriacou a 73 to be equal 99th, and are in danger of missing the halfway cut.
After making bogey on the third hole on Thursday, Lee rebounded with five birdies to trail co-leaders Jiwon Jeon of South Korea and Englishwoman Charley Hull by two strokes.
Scotland's Gemma Dryburgh is joint third, one stroke back, with Korean Mi Hyang Lee after carding first-round five-under 65s.
Lee shares fifth with world No.1 Nelly Korda, fellow American Cheyenne Knight, Spaniard Carlota Giganda, Norway's Celine Borge and Swede Maja Stark.
The West Australian star is provisionally risen to 52nd in the points standings, comfortably inside the Tour Championship qualification cut-off.
Rookie Gabriela Ruffels, her Tour Championship start already secured, and Robyn Choi, are the next-best Australians in a tie for 21st at two under.
Hull, fresh off her first victory in more than two years, didn't lose her form from Saudi Arabia to Florida.
Hull won two weeks ago in the Aramco Team Series-Riyadh, a 54-hole tournament on the Ladies European Tour. It was her first title since winning in Texas on the LPGA Tour in 2022.
"I feel like I've been playing very, very well all year," Hull said. "Sometimes you just forget how to win. So that's kind of reminded me how to win."
It was a great start also for Jeon, particularly her hole-in-one on the par-3 third hole, while she also had six birdies to offset a pair of bogeys.
Jeon hit a hybrid - the equivalent of a 4-iron - on the 182-yard third hole, and unlike some of her previous aces, she actually saw it go in.
"I had exactly the same yardage the last hole for the second shot, so I was talking to my caddie, 'Like just hit the same shot?' Then I hit it and then I saw the one bounce and went in the hole," she said.
"It was very cool to see the hole-in-one actually going into the hole."
Korda hasn't lost much from being out of competition for nearly two months.
The top-ranked player in women's golf had four birdies over her last five holes to salvage a 66 to match Lee.
With The AP