Verizon IndyCar Series championship front-runner Will Power carries a 39-point lead over Team Penske teammate Helio Castroneves into the Shell and Pennzoil Grand Prix of Houston presented by the Greater Houston Honda Dealers.

The makeup of the top five could drastically change though over the next two weekends as three races totaling more than 200 available points will be contested.

The twin 90-lap races on the 1.634-mile, 10-turn temporary street circuit June 28-29 (2 p.m. Central both days on NBCSN) carry full points. Power and Target Chip Ganassi Racing’s Scott Dixon won the races last October – the penultimate event of the season – with Dixon going on to earn his third series title.

It’s the second of three doubleheader weekends this season. Power and Castroneves earned victories at Detroit, with Power amassing 92 total points (victory, runner-up finish and bonus points) and Castroneves 87 (fifth place, win and bonuses).

How the points break down for the 23-car field:

*50 points to each race winner, 40 for second place, 35 for third down to 7 points for 23rd place
*1 point for Verizon P1 Award winner for each race
*1 point for quickest lap in each of the two groups in qualifying for Race 2
*1 point for leading a lap in each race
*2 points for leading the most laps in each race

On July 7, the Pocono INDYCAR 500 fueled by Sunoco is the second of three double points races of the season (Indianapolis 500 and finale at Auto Club Speedway the others). Ryan Hunter-Reay of Andretti Autosport won the 500 Mile Race on May 25 in a late-race duel with Castroneves.

How the points break down for the 22-car field:

*100 points to race winner, 80 for second, 70 for third down to 16 points for 22nd place
*1 point for Verizon P1 Award winner
*1 point for leading a lap
*2 points for leading the most laps

The double-points Indianapolis 500 and the Chevrolet Dual in Detroit doubleheader totaling another 100-plus available points impacted the standings. Power led Hunter-Reay by one point following the inaugural Grand Prix of Indianapolis on May 10, and the gap between first and 10th (Sebastien Bourdais) was 68 points. Scott Dixon was tied with Castroneves for fourth.

Power, who finished eighth in the Indy 500, left Detroit with a 19-point lead over Castroneves. Hunter-Reay fell 27 points back in third, while Dixon tumbled to eighth in the standings. The gap from Power to Bourdais (10th) increased to 197 points. Marco Andretti climbed from seventh to fifth.

Below is how the top five stack up following the Firestone 600 at Texas Motor Speedway (Power the runner-up to Ed Carpenter) and entering the Houston doubleheader, with points earned at the six road/street courses and two ovals: