The result has also extended his series lead to 107 points over Holden veteran Craig Lowndes.
"I made a bit of a bodgy start ... but my crew got me in front,'' the man known as `Frosty' said.
"I wanted to lead going away, not just last night. It's great.''
A win to McLaughlin would've seen history repeat itself - Volvo last won an Australian touring car championship race 28 years ago to the day - with a Kiwi at the helm, no less.
McLaughlin started from pole, his second of the weekend, but this time had the advantage of being the sole driver on the front row.
Tim Slade's Holden stalled moments before the race got underway and was forced to start from pitlane.
It left the path clear for the 20-year-old who, by lap two, held a one-second buffer.
But Winterbottom gradually chewed into his lead after the first round of pitstops - aided by an air hose that come off McLaughlin's helmet and appeared to distract the youngster.
Winterbottom eventually got the better of the S60 and took the lead in pitlane after a well-timed tyre change and fuel top-up.
Lowndes, meanwhile, came in at a lowly 20th, while his Red Bull teammate and defending champion Jamie Whincup finished 10th.
Whincup has not featured on the podium in seven straight races - his longest run without a place in the top three since 2006, his first season at Triple Eight.
The event attracted a bumper 128,255 fans across the Anzac Day long weekend.
-AAP