Updated

(SportsNetwork.com) - The regular season in the NASCAR Sprint Cup Series has reached its midpoint, with 13 races completed and 13 to go before the championship Chase begins.

Right now, nine drivers have virtually guaranteed themselves a spot in the Chase by winning a race this year. That leaves seven positions up for grabs before the regular season concludes on Sept. 12 at Richmond.

Jimmie Johnson scored his series-high fourth victory of the season this past Sunday at Dover. Johnson also has won at Atlanta, Texas and Kansas. Kevin Harvick, the defending Sprint Cup champion, is the only other driver with multiple victories this season. Harvick won at Las Vegas and Phoenix.

Those drivers who have one win this year are Joey Logano (Daytona), Brad Keselowski (Auto Club), Denny Hamlin (Martinsville), Matt Kenseth (Bristol), Kurt Busch (Richmond), Dale Earnhardt Jr. (Talladega) and Carl Edwards (Charlotte).

Martin Truex Jr. (second in the point standings), Jamie McMurray (seventh), Kasey Kahne (eighth), Jeff Gordon (ninth), Aric Almirola (10th), Paul Menard (12th) and Ryan Newman (13th) presently hold positions 10-16 on the provisional "Chase Grid."

Truex is having the best start in his Sprint Cup career, with three top-five finishes and 12 top-10s. He has led the most laps in each of the last three races but has come up short of winning. His second and most recent victory in the series occurred nearly two years ago at the Sonoma, California, road course (69 races ago).

"Right now, we have momentum where our cars are working well," Truex said. "I feel like we can go anywhere and have a shot at winning."

Even if Truex doesn't win a race during the regular season, it's a pretty good bet he will make Chase. His last appearance in the playoffs was in 2012, driving for Michael Waltrip Racing at the time. Truex is in his second season with Furniture Row Racing, a single-car team.

McMurray has been winless in the last 53 races. He's hoping this will be the first year he makes the Chase.

Last year, Kahne won the penultimate race of the regular season -- Atlanta -- to earn a spot in the playoffs. He has not been to victory lane in Sprint Cup since then. Kahne is coming off a season-best finish of fourth at Dover.

Gordon is in his 23rd and final season of competition in NASCAR's premier series. He won three races during the regular season in 2014 -- Kansas, Indianapolis and Michigan. Gordon had a rough start this season, finishing 33rd, 41st and 18th in the first three races and sitting 30th in points. But the four-time series champion has bounced back with eight top-10 finishes in the last 10 events.

"I think we are very conscious of the fact that we need to improve our performance," Gordon said. "We have not lived up to our own expectations, and we are working extremely hard to find that. I think right now that if we execute flawlessly, we have a shot at winning. But we haven't been doing that, either. We have some work to do."

The next race is on Sunday at Pocono, where Gordon holds the track record for most wins with six. His most recent victory there happened in August 2012. Earnhardt, who is Gordon's teammate at Hendrick Motorsports, scored a season- sweep at Pocono in 2014.

Almirola is trying to make the Chase for the second year in a row. His victory in the rain-shortened July race at Daytona last year earned him a spot in the playoffs for the first time in his career.

Menard is another driver hoping for his inaugural appearance in the Chase. His lone win in the series happened in July 2011 at Indianapolis. Menard is just three points ahead of Newman, who occupies the final spot on the 16-driver Chase Grid.

Newman finished a career-best second in the Chase standings in 2014, only one point behind Harvick. It's been 65 races since Newman's last win (July 2013 at Indianapolis).

Clint Bowyer is the first driver on the outside of the Chase Grid, as he currently sits 17th in the point standings. Bowyer trails Newman by 37 points. Next in line are: Danica Patrick (48 behind Newman), Greg Biffle (58 behind) and Kyle Larson (72 behind).

Larson's third-place run at Dover marked his best finish of the season and it moved him up two spots in the point standings. He was sidelined for the March 29 race at Martinsville due to a fainting spell the day prior.

"Our first good run of the year," Larson said at Dover. "Hopefully, this will kind of transition into some momentum for us, for our team, and we can start getting some more top-five and top-10 finishes."

Larson is in his second full season of Sprint Cup competition. He has yet to win a race in the series.

Those drivers ranked 21-30 in the point standings are A.J. Allmendinger, Casey Mears, David Ragan, Austin Dillon, Sam Hornish Jr., David Gilliland, Ricky Stenhouse Jr., Tony Stewart, Cole Whitt and Justin Allgaier.

Allmendinger won on the Watkins Glen, New York road course last August, which gave him a spot in the Chase for the first time.

Any driver who wins a race during the regular season must be ranked in the top-30 in points after the fall event at Richmond in order to qualify for the playoffs.

After missing the first 11 races this season due to a broken right leg and left foot at Daytona in February, Kyle Busch is trying to win one of the remaining 13 events and place himself in the top 30 in points after Richmond. Busch finished 11th at Charlotte and scored his first 33 points of the season. At Dover, he placed 36th after being involved in an accident with Brian Scott late in the race. He had been running among the top 10 for most of the day.

"This isn't what we need," Busch said after his incident with Scott. "We weren't going to win (Sunday), but it doesn't help when you go from likely finishing third all the way to where we ended up."

Busch is 168 points behind 30th-place Allgaier in the rankings.