He grabbed the yellow jersey on Stage 2 almost three weeks ago, and has worn it for all but two stages. A largely ceremonial final ride into Paris awaits on Sunday.
"It's really difficult to explain all the emotions that I've gone through in these last three weeks. But as time goes by, maybe I'll find the words to describe what I'm feeling," Nibali said through a translator. "Perhaps on the Champs-Elysees, I'll realize a little bit more.
"This year was a great race. It was almost made to measure for me," he said of the ride through the hills and dales of Yorkshire, England, over cobblestones in northern France, and over mountain passes in the Alps and Pyrenees.
For days, Nibali's domination has reduced the drama to who would join him on the final podium on Sunday. The Stage 20 time trial solved that: Jean-Christophe Peraud and Thibaut Pinot.
They will be the first Frenchman to medal in France's beloved race since Richard Virenque in 1997.
The duo did enough to leave behind an unlucky Alejandro Valverde of Spain in their three-man race for the final podium. Only 15 seconds separated them when the stage began in Bergerac, but it became more than two minutes when the time trial finished in Perigueux.
Peraud, a 37-year-old former mountain bike racer, became tearful at the finish after learning he would be the Tour runner-up: "It's beautiful," he said.
Also, American Tejay van Garderen climbed a spot from sixth to fifth overall by overcoming a deficit of 2 minutes, 7 seconds to Romain Bardet by two seconds. The young French rider lost key seconds after blowing a flat at the end of the stage.
Tour de France Stage 21 preview
O Sunday, 7 a.m. TV • NBCSN
An 85-mile, largely ceremonial procession from Evry to Paris. After nine laps of the Champs Elysees, sprinters such as Marcel Kittel, Peter Sagan and Alexander Kristoff will look to leave their mark in the finale.
LEADERS • 1. Vincenzo Nibali, Italy, 86 hours, 37 minutes, 52 seconds. 2. Jean-Christophe Peraud, France, 7:52. 3. Thibaut Pinot, France, 8:24. Also • 5. Tejay van Garderen, United States, 11:44.