Kaufman shot a 2-under-par 69 on Friday and is at 3-under 139 heading into the final two rounds.
Henderson birdied Nos. 12 and 13 and closed with five pars.
"Obviously I saw (Henderson) playing good, and when she's on, it's hard to beat her but I'm excited to keep fighting", said Ciganda, a two-time LPGA victor.
Ko's two-round total of 136 leaves her six strokes shy of Henderson, who fired a four-under 67 which included three bogeys to maintain her two-stroke lead. "And going into the back nine, I just wanted to give myself as many chances as I could". He made three birdies and an eagle in his round Friday.
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Western officials say most insider attacks stem from personal grudges and cultural misunderstandings rather than insurgent plots. NATO's Resolute Support later tweeted that seven USA servicemembers were wounded and evacuated for treatment.
"I felt like today was going to be a really good day", she said. "It's exciting. I'll just need to go out there and play well tomorrow". I was hitting the ball really well and some putts were dropping, which (was) kind of a change from the past few weeks. "It's been a little bit of a rough season so far, not getting the results that I've been looking for but this week seems to be a turnaround week and hopefully I can just finish strong the next two days", Henderson told reporters.
Ko's 85-week reign as world No.1 ended earlier this week when Thai golfer Ariya Jutanugarn won the Manulife Classic in Cambridge, Ontario.
But the new world No.1 has had a slow start in MI, carding back-to-back rounds of two-under 69 to share 30th place with 11 others.
Lexi Thompson shot a 64 on the Blythefield layout reduced to a par of 69 because of flooding, giving her a one-stroke lead.
New Zealand's Lydio Ko finished the tournament in a tie for tenth after a final round one-under 68 while Australia's Sarah Jane Smith finished in a tie for 37th. "It's made me play better the last couple of years".