While the 2009 Atlantic Championship may only have raced four times since the season-opener at Sebring in March, the pace is about to pick up rapidly, beginning with Saturday's race at Lime Rock Park.

The series will contest six races in the 44 days that separate the Northeast Grand Prix and the race at Mosport International Raceway on 30 August, and those races will undoubtedly go a long way toward determining the 2009 series champion. With one-third of the season already in the books, however, the championship battle remains close, with just 16 points separating the top four drivers.

Leading the way is the only woman driver in the field, as 20-year old Swiss racer Simona de Silvestro has come into her own behind the wheel of the #78 Team Stargate Worlds entry. de Silvestro is the only driver in the series to celebrate multiple victories thus far, with dominating wins from pole position in both round two at Miller Motorsports Park in May and round four at New Jersey Motorsports Park last month. The third-year Atlantic racer leads second-year racer Jonathan Summerton by eight points heading into round five.

The 21-year-old Floridian picked up his first victory of the season in the opening race of the New Jersey double-header last month, and has finished on the podium in three of the four races in addition to earning a pair of pole positions. However, after running the first part of the '09 campaign with Genoa, Summerton will reunite with Newman Wachs Racing this weekend, piloting the #34 entry for the team that took him to second in the championship in his rookie Atlantic campaign.

While Summerton is looking to pass de Silvestro for the championship lead, he must also pay close attention to Newman Wachs team-mate John Edwards, who is just five points back in third place. The 18-year old opened the 2009 season with his first career victory and has finished sixth or better in all four of his starts this season.

Belgian rookie Frederic Vervisch has quickly made a name for himself in Atlantics, with podium performances in three of his four starts and a best run of second in the Sebring season opener. Vervisch, who drives the #17 machine for Genoa Racing, is currently fourth in the overall standings and leads the rookie of the year competition by 20 points over Borja Garcia.

Garcia, meanwhile, picked up his first Atlantic podium with a third-place run in the first race at New Jersey and is now fifth in the championship as he returns to the cockpit of Condor Motorsports' #6 machine. Garcia has a total of 32 points, the same amount as Estonian Tonis Kasemets, who has finished seventh or better in all four of his starts in 2009. Kasemets, whose best result of the season was a fifth-place run at Miller Motorsports Park, will once again pilot the #35 Fatburner entry for Polestar Motor Racing this weekend.

One point behind the fifth-place tie is defending series champion Markus Niemela, who moves to the #2 Jensen MotorSport machine this weekend after driving for Newman Wachs Racing in the first four races of the season. After a slow start to the season, Niemela scored a pair of fourth-place results in New Jersey last month, but ran into budget problems just as his campaign was looking up.

Two points behind Niemela is de Silvestro's team-mate, former child actor Frankie Muniz, who picked up the best result of his three-year Atlantic career in May with a fourth-place performance in the #77 entry at Miller Motorsports Park.

British rookie James Winslow is ninth in the standings and finally finds some continuity in his campaign as he is once again entered in the #18 CARS Motorsport machine for Genoa Racing. Winslow's best results to date are eighth-place performances from Sebring and Miller but hopes that the stability of remaining with the same team for a second straight meeting will help push him up the order.

Max Lefevre completes the top ten in the standings heading into this weekend's fifth round, the French rookie - who missed the opening race of the season due to illness - returning to the #7 machine for Condor Motorsports.

This weekend's race at Lime Rock will see the return of both Conquest Racing and New York's Matt Lee for the first time since Sebring. In that event, Lee scored the best result of his Atlantic career with a ninth-place run for Jensen MotorSport, while the Conquest team finished fourth with Latvian Harald Schlegelmilch and eighth with Winslow, with Lee slipping into the #12 car previously piloted by the Briton.

American rookie Michael Nacol makes his fifth professional race start this weekend in the #3 machine for Jensen MotorSport, looking to improve on a tenth-place performance in, while Richard Zober will also be back in the #66 Zober Industries machine run by Polestar.