The Raiders, in a strictly preliminary form, reintroduced themselves to the East Bay on Thursday night. The action was sloppy, the weather comfortable, the atmosphere festive.

Or about as festive as could be mustered by the 15,000 or so devoted souls who showed up for an evening of NFL exhibition football at the O.co Coliseum.

Those in attendance for this down-to-the-wire, 24-18 loss to Arizona witnessed two possessions from Oakland’s starting units.

They received tantalizing glimpses of rookie wide receiver Denarius Moore, the fifth-round pick who has been a training-camp sensation. They watched young Raiders cornerbacks get schooled by the Cardinals’ passing game.

They also saw plenty of penalty flags from the ugly play that was expected in the wake of a lockout that denied NFL teams the ritual of offseason meetings and workouts.

“We’ll figure out the things we’ve got to continue to work on, the things we’ve got to continue to improve,” Raiders quarterback Jason Campbell said. “That’s what the preseason is for.”

As for the 45,000 or so who failed to show for Hue Jackson’s preseason debut as Oakland head coach — resulting in a depressing turnout under any circumstances — at least five distinct possibilities exist.

One, it is an exhibition game and therefore a desultory sham of an event not worth the time or money.

Two, household cash flow has diminished to a trickle that dries up after barely covering food, rent and utilities.

Three, they’re still displeased with the NFL over the offseason lockout mess.

Four, they’re boycotting in support of Tom Cable, the coach fired by owner Al Davis after last season.

Five, they’re not budging until the Raiders earn a portion of the monthly budget.

While all these factors likely are part of the equation, the Raiders can directly influence only one. They can’t unilaterally abolish preseason football, aren’t in reasonable position to reduce ticket prices, can’t do anything to eradicate instantly any lingering bitterness over the old labor beef and won’t be rehiring Cable.

They can, however, do something to seduce the fan.

To have a chance at turning most of those empty seats into warm bodies eager to support them, the Raiders will have to prove themselves to be a legitimate contender.

For those fans whose loyalties and collective will have been beaten down by years of dreadful-to-mediocre football, submitted by five dramatically different coaches, these Raiders will have to show they are appreciably better, or at least more distinctive, than the previous eight versions.

Jackson has been consistent in saying this team will be different, that it will improve on last season’s 8-8 record that was Oakland’s best since 2002. So confident is the coach in vowing improvement, he’s practically ensuring a turnaround.

There were signs he might be onto something. Rookie tight end David Ausberry made a nice catch and toe-drag to stay inbounds on an 18-yard touchdown pass from Trent Edwards, the Stanford product battling Cal product Kyle Boller for the No. 2 quarterback spot.

Oakland’s starting pass rushers, impressive last season, appear to have lost nothing.

“We still have ways to go,” defensive tackle Richard Seymour said. “But I felt it was a pretty good start for us.”

But a few, scattered signs of encouragement now may not be enough to reignite the passion of those fans not yet feeling it — or unable to afford the feeling. They’ve seen it before.

Art Shell’s 2006 Raiders went 4-1 in the preseason, convincing some the Raiders were back. They sold out the season opener against San Diego, lost 27-0 and — even despite drawing five consecutive home crowds above 60,000 — finished the regular season with a Davis-era worst 2-14 record. Such bitter memories have a way of staying in the gut.

That’s the kind of history Jackson is trying to buck. What he has for now is a work in the early stages of progress. The Raiders have a perceptible level of talent and requisite desire, but they are long on youth and short on field leadership, particularly on offense.

The lockout did them no favors, but that applies to every team in the league.

This game was more of a scrimmage, something to evaluate in the process of shaping the roster.

“I was kind of hoping we would be out there a little longer,” cornerback Stanford Routt said. “But it was the coaches’ call, so we had to go ahead and sit it down.

“But I can’t wait until next week for the Battle of the Bay.”

Maybe that’ll get the fans to dig around the seat cushions and coffee cans for enough green to buy tickets. Meanwhile, a good many are in full-blown show-me mode.

Contact Monte Poole at mpoole@bayareanewsgroup.com.