Penske is hoping to expand Juan Pablo Montoya's NASCAR programme in 2015 alongside his IndyCar deal.
The Colombian returned to IndyCar with Penske this year after a six-year stint in NASCAR with Ganassi.
Team owner Roger Penske told AUTOSPORT that Kurt Busch's success at the Indianapolis 500 - where he finished sixth with Andretti before returning to Charlotte later that day for the NASCAR Sprint Cup race, where he retired with engine failure - could open the door for more IndyCar/NASCAR crossovers, including from within his team.
"I think Kurt has done a great job ... and others will see it as an opportunity," Penske said.
"I'm sure that there are a lot of guys in NASCAR who'd like to come here [to IndyCar], and vice versa.
"We've talked about how if Montoya likes what he's doing here, maybe we'll run Montoya in both places in 2015. You never know. So we might come the other way."
Montoya is already confirmed to be dovetailing a limited NASCAR programme with his IndyCar commitments this year, with Penske preparing to run the Colombian at the Brickyard and Michigan Cup races.
As the only other team to field cars in both IndyCar and NASCAR, Ganassi would be another obvious candidate for an overlapping programme.
The team's managing director Mike Hull told AUTOSPORT that he is open to the idea of an attempt at the Indy/Charlotte double, but that there have been no discussions for 2015 yet.
"We'd consider it, but I think it's way too early to talk about it," he said.
"We're in the middle of our seasons - sportscar, IndyCar and NASCAR - and Kyle Larson's sort of doing the double because he is doing Nationwide and Cup now. I think it's too early to talk about it."