World No.2 Korda will be playing in the final group for a third straight week and coming off a win at the Tournament of Champions followed by two runner-up finishes behind Hyo Joo Kim.
She shot a five under 67 at difficult Shadow Creek in Las Vegas on Saturday to close on fellow American Coughlin, who battled to a 73 to lead at seven under in the rich event co-sanctioned by the LPGA Tour and Ladies European Tour.
There have been plenty of signs the 27-year-old Korda is closer to the form that brought her seven wins and Player of the Year honours two years ago - certainly better than last year when she failed to win.
"I'm just playing really good golf," Korda said. "I have always worked really, really hard, but I'm proud of the work that I've put in the past few weeks when I didn't go to Asia when the tour was there. I just feel refreshed, happy.
"Last year was just a weird year where stuff was just not going my way by like centimetres. That wears on you, and that's why I like taking like longer breaks."
Coughlin had threatened to run away with the championship over the first two days but, with just five players stiill under par, was happy to be in front.
Denmark's Nanna Koerstz Madsen (71) and Japan's Miyu Yamashita (71) were each 3 under and Ireland's Leona Maguire (74) was 1 under.
"This golf course is really, really hard, especially if you get in the wrong spot," Coughlin said.
"I felt like I did a pretty good job today of at least getting in spots, and if did get a little out, making sure I walked away with no worse than bogey."
Karis Davidson shot a 70 to be in seventh at 1 over with fellow Australians Grace Kim (77) tied 20th at 5 over and Gabriela Ruffels (76) tied 26th, 6 over.
Hyo Joo Kim almost certainly won't extend her LPGA Tour winning streak to three after ropped from a tie for second all the way down to a tie for 17th at 4 over after a 79.
Being withing striking is one thing in this loaded event, which has a $US4 million purse. Making an actual charge on this course is another.
Coughlin last won in 2024, finishing first in Canada and Scotland.
She almost won at Shadow Creek last year, when it was a match-play event. Coughlin made it to the final pairing before losing to Madelene Sagstrom.
"There are a few holes that you can make birdies, like the par 5s, 11, 12," Coughlin said. "So trying to take advantage when you can and just holding on for dear life on the other holes."