The French driver, behind the wheel of a Toyota Yaris, has been victorious in Portugal on five occasions -- 2010, 2011, 2013, 2014 and 2017.
Another triumph on Sunday will take him one ahead of Finland's Markku Alen, also a five-time champion with Fiat and Lancia in the 1970s and 1980s.
Ogier, who is only racing part-time in the 2024 world championship, goes into the final day's four stages with an 11.9sec lead over Ott Tanak.
The Estonian driver briefly led the rally on Saturday in his Hyundai.
Belgium's Thierry Neuville, in another Hyundai, is third overnight, more than a minute behind Ogier.
Reigning world champion Kalle Rovanpera, a teammate of Ogier at Toyota, had been ahead on Friday but endured a Saturday to forget.
He misjudged a right-hander on stage 11 and rolled his vehicle, sending him out of contention.
Japan's Takamoto Katsuta, who had been sitting third on Friday, also saw his hopes hit when his Toyota suffered a broken suspension.
"It's been a good day," said Ogier. "A tricky one, we didn't expect so many things happening today.
"Unfortunately on Toyota's side it was not a perfect day. For me it was good, but we lost two cars. We have to try and finish the job tomorrow now."
Standings after Saturday's stages:
1. Sebastien Ogier/Vincent Landais (FRA/Toyota) 3h01:55.8, 2. Ott Tanak/Martin Jarveoja (EST/Hyundai) at 11.9, 3. Thierry Neuville/Martin Wydaeghe (BEL/Hyundai) 1:11.4, 4. Daniel Sordo/Candido Carrera (ESP/Hyundai) 1:25.6, 5. Adrien Fourmaux/Alexandre Coria (FRA/Ford) 1:32.9
