He's the driver ready to replace Martin in the No. 01 Chevrolet when the series moves to Bristol Motor Speedway on March 25.
"When I go to Las Vegas [next week] I might put a couple of dollars on it," Smith said before practice for Sunday's Busch Series race at the Autodromo Hermanos Rodriguez. "I'm sure it's going to be on the board soon. It's a pretty big story.
"I don't know what the odds are. All I can say is if I was in his shoes and leading the points after Atlanta it would be tough for me as a driver to get out of the car."
Either way, Smith will have a ride at Bristol.
Owners Jay Frye and Bobby Ginn have promised to put him in a fourth car, the No. 39, if Martin has a change of heart. They've even discussed using his Busch Series crew chief to run the show.
"If he stays in it that's awesome for the team and it's awesome for our company as a whole," Smith said. "If he decides to get out of it I'm going to do my best to keep it running as well as he's been running."
Martin, off to the best start in his Cup career with a second in the Daytona 500 and fifth last week at California, has been adamant that he won't change his mind. He insists he's happy with the part-time schedule and that he's looking forward to having an off weekend.
He also has a history of changing his mind. He extended his 2005 retirement tour at Roush Fenway Racing into 2006 after owner Jack Roush lost Kurt Busch to Penske Racing.
"I think it's going to be a split-second decision," Smith said. "I think he'll decide after the race at Atlanta. You've just got to go with your heart at that point."
Smith has run through all the scenarios, including what would happen if the No. 01 was in the top 12 in points with him and Martin splitting the schedule.
"How cool would that be?" Smith said. "Maybe it would put some pressure on NASCAR to make a decision."
There would be no decision. The way the Chase for the Nextel Cup is set up the top 12 in driver points make the field. Smith and Martin could run the car for the owner's title, but not the overall championship.
"That was one of the goals we talked about at the beginning of the season," Smith said.
Martin leading the points and driving a full season wasn't discussed.
"Did anybody think Mark would be this strong switching teams?" Smith said. "It's tough to switch teams. A lot of times it takes a while to get the communication down. That's why within the organization it hasn't been that big of a deal."
But, Smith added, it could be if Martin continues to stay near the points lead.
"Obviously, it's a good story right now," he said. "It's going to be an even better story if we get to Bristol and he's leading the points.
"I want to be in that car and I'm real excited about it. The other part of me says that if I was in his shoes there's not a chance in heck I would get out of that thing."
David Newton covers NASCAR for ESPN.com. He can be reached at firstname.lastname@example.org.