Ewing, who held a one-shot lead following an opening 68 completed late on Thursday, was among the early starters on Friday and stormed clear of the field with a birdie on the third and four in a row from the sixth to be out in 30.
The 30-year-old from Mississippi also picked up further shots on the 11th and 16th before dropping her only shot of the day on the last to complete a superb 66 at Walton Heath.
At 10 under par Ewing enjoyed a five-shot lead over compatriot Andrea Lee, home favourite Charley Hull and Japan’s Minami Katsu, with South Korea’s Kim Hyo-Joo, Lilia Vu, Alison Lee and Gaby Lopez all on four under.
The similarities with Harman’s victory at Royal Liverpool were hard to ignore, with Harman leading by five at halfway on 10 under, maintaining his advantage following the third round and eventually winning by six.
Ewing also revealed she shared Harman’s much-publicised passion for hunting, along with a nickname for their different college teams.
“He’s a bulldog but he’s a Georgia bulldog,” Ewing said. “I’m a Mississippi State Bulldog. I guess we have that in common.
“But yeah, it’s pretty cool, southern guy, I’m southern, just a little Mississippi girl. It is inspiring, what he did.
“I actually do some hunting. I know that’s probably not going to be interpreted well by the media but I do, yes. For the most part my family, my husband and I, we do mostly deer hunting, so venison.”
Asked what it would mean to win a maiden major title this weekend, Ewing added: “It would be huge. It’s something I’ve obviously circled as something I want to accomplish in my career.
“I’ve had possible chances to do that, I’ve been in the last group, so for me it’s just going to be (about) leaning on that a little bit as well as leaning on the confidence I have in my game right now.”
Hull followed an opening 71 with four birdies in a flawless second round of 68 as she overcame the changeable conditions for the afternoon starters.
“It was quite tricky out there today,” Hull said. “It was a bit windy, a bit rainy, we had a bit of all the four seasons out there.
“But I’m pretty happy and it was good to finish with a few birdies coming in. It was quite hard to hit it close to the pins because it was windy and I’m hitting a bit of a draw at the minute.
“But I’m happy how I hit it off the tee and holed some long putts and I’m buzzing for the next few rounds.”
Vu won the first major of the year, the Chevron Championship, in April, but a tie for 35th in last week’s Scottish Open is her best finish in a strokeplay event since then.
“I feel like post-Chevron Championship I’ve been struggling a little bit and to finally, hopefully, be in contention by the end of today just feels really rewarding,” Vu said.
“I think every time I get in my own way, it’s when I’m too focused on winning.
“But if I just focus on playing my game then I’m in a good position to try and win instead of just getting really upset if I mess up on a hole, and I did that last week.
“I got upset when I was playing well, and then just couldn’t hold it together after because I thought it was just over. And I’m just trying to be in a better mindset this week.”