The number 31 Cadillac leads the 62nd Daytona 24 hours endurance race at the halfway point, with Jack Aitken at the wheel 1.7 seconds ahead of Laurens Vanthoor in the number 6 Penske Porsche.
The pair swapped positions throughout the first six hours of the race, with Aitken passing number 7 driver Dane Cameron while negotiating slow traffic.
In GTP there were several competitors that suffered from problems that affected their own chances, including the number 10 Wayne Taylor Racing Andretti Acura driven by Felipe Alburquerque.
The car returned to the track after the team replaced a wiring harness, but was nearly 100 laps down on the pace. A similar issue also plagued the number 40 Andretti Acura with Louis Deletraz at the wheel, but he only lost a lap after help from the track safety teams.
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Button takes to the track
The 2009 Formula 1 World Champion Jenson Button got his first taste of the Daytona 24 hours with a triple stint in the middle of the night, at the wheel of the number 40 Wayne Taylor Racing car he shared with Deletraz, Jordan Taylor, and Colton Herta.
Button had a short off-track excursion after light contact with the number 3 Corvette Racing GT3 driven by Alex Sims, but there was no major issue for the Briton ahead of his full WEC season.