The race for class championship honors in the IMSA WeatherTech Championship is heating up as the 2017 season begins to wind down.

The closest battle can be found in the GT Le Mans (GTLM) class, where No. 3 Corvette Racing Chevrolet Corvette C7.R co-drivers Antonio Garcia and Jan Magnussen currently hold an eight-point lead over last weekend’s GTLM winners at the Continental Tire Road Race Showcase at Road America, No. 66 Ford Chip Ganassi Racing Ford GT teammates Joey Hand and Dirk Mueller.

Garcia and Magnussen have 239 points, while Hand and Mueller have 231 and No. 25 BMW Team RLL BMW M6 GTLM co-drivers Bill Auberlen and Alexander Sims are just one additional point back with 230 markers. A second Ford GT, the No. 67 entry for Richard Westbrook and Ryan Briscoe is relatively close as well, trailing the leader by just 14 points.

The GTLM manufacturer battle, however, has a different leader and is a much closer race. Ford leads with 254 points, one ahead of Chevrolet’s 253 markers.

Defending GT Daytona (GTD) champions Alessandro Balzan and Christina Nielsen – who co-drive the No. 63 Scuderia Corsa Ferrari 488 GT3 – continue to benefit from outstanding consistency to lead the standings by 15 points, 254-239, over No. 33 Riley Motorsports-Team AMG Mercedes-AMG GT3 co-drivers Ben Keating and Jeroen Bleekemolen.

Ferrari – which has only one full-time entry in the GTD class – also leads the manufacturer standings by one point, 264-263, over Mercedes-AMG, with Porsche seven points back at 257.

The Prototype class battle, which had tightened up somewhat recently, has been stretched to a 26-point advantage, 258-232, for No. 10 Konica Minolta Cadillac DPi-V.R co-drivers Ricky and Jordan Taylor over two-time Prototype class champions Joao Barbosa and Christian Fittipaldi in the No. 5 Mustang Sampling Cadillac DPi.

The Taylor brothers, who opened the season with five consecutive victories and returned to the podium last weekend with a second-place run at Road America, will clinch the 2017 title if they depart the next Prototype event – the Continental Tire Monterey Grand Prix at Mazda Raceway Laguna Seca on Sept. 24 – with a lead of 37 points or greater.

In the Prototype manufacturer standings, Cadillac has a 24-point lead, 277-253, over Nissan, which picked up its first WeatherTech Championship victory of the Daytona Prototype international (DPi) era last Sunday at Road America with No. 22 Tequila Patrón ESM co-drivers Pipo Derani and Johannes van Overbeek.