Joey Logano a candidate for No. 22

Roger Penske also didn't rule out expanding from two to three cars and including Sam Hornish Jr., who has been in the No. 22 since AJ Allmendinger was suspended and ultimately released for violating NASCAR's substance-abuse policy, in the mix for next season.

Penske said he hoped to have a decision by the Sept. 16 Chase opener at Chicagoland.

Sources close to the situation said Logano, who is in the final year of his contract with Joe Gibbs Racing, is the frontrunner for the No. 22. Logano told ESPN.com recently he has two offers for 2013, and that one was from JGR.

The issue at JGR is finding a full-time sponsor.

"He's obviously a candidate, but there's other good people, too, that people haven't talked about," Penske said before the Sprint Cup race at Bristol Motor Speedway. "We have a couple of rabbits."

Penske would not expand on other potential candidates.

"There are no commitments at this point," Penske said. "We've got to play this by ear. Sam has done a good job, so we've really got to wait and see how this thing plays out."

Hornish has finished 12th and fifth in his past two Cup starts before Bristol in the Shell Pennzoil car. He also is third in the Nationwide Series standings.

Penske didn't rule out that Alliance Truck Parts, which sponsors Hornish's Nationwide car, could move up to Cup in 2013.

"We're just glad Alliance is coming back," Penske said. "Those are things we're checking in the box, all the sponsors, who wants to step up at what level and then return who will be the driver.

"You just don't make a decision like this (fast). Sam is running well. We've got sponsors. We've got to decide if we run three cars next year, do we run two. More time gives us more knowledge on exactly where we want to be."

Gibbs Racing president J.D. Gibbs told ESPN.com he believes the organization still has a chance to keep Logano. He also admitted the organization hasn't come up with a sponsor to give Logano the full Cup ride in 2013 that Logano wants.

JGR's offer is for a fulltime Nationwide Series ride and part-time Cup schedule.

"He was OK with that until another opportunity came up," Gibbs said.

That opportunity was the No. 22 team that is fully sponsored by Shell Pennzoil.

"He's looking at other possibilities," Gibbs said. "We would love to keep him in the fold. We're still not at the point of announcing things."

Logano is on the outside looking in at JGR because the organization, according to sources, has signed Matt Kenseth to the No. 20 team next year. Neither Kenseth nor Gibbs would admit to the deal, but both said an announcement should come in the next two weeks.