The American was one of the lucky 32 players who had already completed their rounds on Friday, posting a 12-under-par 128 total before afternoon thunderstorms ended play for the day.
The rest of the field, except for 10 players who withdrew, returned early on Saturday to the TPC Southwind but nobody went close to catching Crane despite ideal scoring conditions.
South African Retief Goosen (66) and Colombian Camilo Villegas (64) performed best, sharing second place on eight-under.
Phil Mickelson, who next week hopes to complete a grand slam of major victories by winning the U.S. Open in North Carolina, shot a 68 to trail Crane by seven strokes.
After the cut was made at level-par 140, the players who survived headed straight back out for a third round that will not be completed until Sunday morning.
"It was a good solid round but it wasn't what I was hoping for," Mickelson told reporters.
"Course conditions were pretty easy today, gave us a lot of birdie opportunities, but I wasn't able to hit my iron shots close enough to take advantage."
Mickelson was unconcerned about the prospect of the St Jude Classic being finished on Monday.
"I think the best way to get ready for next week's U.S. Open is to get in contention, have an opportunity to win, and if that goes into Monday so be it," he said.
"Once that's done all I have to do is get my game sharp. Having the tournament go to Monday, even Tuesday, is not detrimental I don't think."
- Sports & Recreation
- Camilo Villegas