I've racked my brains for months on this and because of the well-documented lack of public money in - and around - Tampa, I just don't see the Rays ever getting a new stadium in Hillsborough County. Can't happen without public money.
UNLESS, one somewhat far-fetched scenario plays out.
The only way I could see the Rays moving across Tampa Bay is if the Seminole Indian tribe builds them a new stadium out at the Hard Rock Casino. This may not be the tribe's first experience with stadium-building, but if they decided that a $500 million investment would result in more visitors and revenues at the casino, I suspect they could try to make a deal.
That doesn't mean it's a likely scenario. St. Pete would sue to keep the team. The Rays would have to alienate a portion of their fans. Things would get ugly. Major League Baseball would have to sign off on the deal. The state would get involved too and have to essentially choose its relationship with the Seminoles over its relationship with St. Pete.
But, I guess anything's possible.