Troxel's hold on Top Fuel getting loose

This weekend's 10th O'Reilly Midwest Nationals at Gateway International Raceway in Madison, Ill. -- just east of St. Louis -- will usher in the only night race on the NHRA POWERade schedule.

It's an event which gets racers and fans equally amped up, as the visual splendor of the four professional classes charging side by side under the lights is something even the most jaded drag racing devotee can never get enough of.

As the season moves into its second half, and the recent three-races-in-three-weeks marathon concludes in Madison, the race itself will have special significance.

Here's a preview of this weekend's quarter-mile spectacle.

Top Fuel

Doug Kalitta missed a golden opportunity to tighten the championship chase even further in Englishtown last Sunday when he dropped his second-round race against eventual event winner "Hot Rod" Fuller after watching points leader Melanie Troxel get upended in Round 1 by Larry Dixon -- her first opening-round loss of 2006. The margin between Troxel and Kalitta is now only 48 points.

Kalitta had been riding a hot streak, winning four of five races heading into E-town and it would be a mistake to think he and his team have lost all of their momentum. The onus is pointed more in the direction of Troxel, whose first-half string of final-round appearances and two national event wins powered her to the top spot. But her recent struggles have left her vulnerable, and Kalitta may not be her only concern.

Brandon Bernstein -- the No. 1 qualifier in E-town -- has quietly moved to within 155 points of Troxel, which equates to around eight rounds of racing. He comes into Madison as the defending event champion and will be inspired to do well in the hometown of the team's longtime sponsor, Anheuser-Busch.

Suggestion? Keep your eye on the three aforementioned front-runners this weekend.

Funny Car

Ron Capps' victory in Englishtown last week was no less than monumental. The key to winning any POWERade championship is, of course, piling up round wins at every event. But another crucial ingredient is taking advantage of the misfortunes of your competition when the opportunities present themselves. Capps did precisely that in E-town by winning the race as all three of his closest pursuers in the points -- John Force, Robert Hight and Eric Medlen -- were all off the board by the end of Round 2.

Capps is the defending event champion, and in a more historical vein, remembers winning his first national event in a Funny Car here in 1997. In short, everything seems to be going his way as the second half of the season begins. No need to overanalyze this situation. Capps has rebuilt his points lead into triple digits (106), has been as consistent as any driver has ever been in the category, and remains focused on doing his job while avoiding any childish trash talk or cocky hubris.

If anyone in the class wants to make a real battle out of this year's title chase, they had better make some strong moves right now -- especially Force, who has the best chance mathematically to pressure the Brut driver. This weekend may set the tone for the entire second half of the schedule.

Pro Stock

While the Funny Car championship picture appears to be a two-car adventure at present, so does Pro Stock -- except in this case, both cars are from the same team.

Jason Line currently has a solid grip on second place in the POWERade standings, 37 points behind his teammate and three-time champion Greg Anderson. By now, everyone in the class knows that the relative parity we've seen this season as opposed to the lack of it in the past several campaigns is not a fluke, and yet, Anderson and Line are up top. But their success this year is a function of their consistency rather than their dominance, which means it's still anyone's championship to win.

The top five drivers are within striking distance of Anderson, not the least of which is Kurt Johnson, the defending Madison champion, who'll be looking to rebound from a disappointing showing in E-town last week.

So will Jim Yates, third in the points and only 91 markers behind Anderson. But in the minds of many, Dave Connolly, fourth in the standings and 106 points out of first, may be the driver to watch in the second half. He came closer than anyone else to defeating Line last weekend in a paper-thin .0330-second final-round decision, and Connolly continues to be one of the most bankable drivers in the category when ranking reaction times.

Anderson and Line know that trouble could be waiting at their back door.

Pro Stock Motorcycle

Matt Smith's first career national event win at last weekend's Supernationals commanded the spotlight at least for the moment. But as the teams head for Madison, the bigger story now becomes the re-emergence of the Harley-Davidson and Buell after Suzuki's early season monopoly. The points standings now reflect the overall parity at which the bikes have arrived.

Angelle Sampey leads the standings by a scant 12 points, helped along by the winless record that second-place rider and defending POWERade champion Andrew Hines has been saddled with this year. Sampey's teammate, Antron Brown, is third, another Suzuki racer, Karen Stoffer, holds down fourth and Smith's Buell has taken him to fifth. Total spread from first to fifth? Only 117 points.

The American bikes have now won the last two events. Hines was last year's low qualifier on his Harley V-Rod in Madison, but it was an all-U.S. Army final as Sampey outran Brown for the event title.

Picking a winner this year has been next to impossible and right now, the vibe leans toward three distinct possibilities. Hines will finally get that first win of '06, another dark horse (a la Ryan Schnitz in Joliet or Smith in E-town) will ambush the Big Dogs, or the U.S. Army team will end its two-race slump and get healthy again.

Bill Stephens covers NHRA for ESPN.com.