Organizers of today's Preakness Stakes will be watching anxiously to see whether fans turn out in the record numbers they did last year, despite heightened security and a forecast of early rain.
Pimlico Race Course's grandstand and clubhouse areas are sold out, while most of the tickets for the infield are bought on race day. The infield accounts for about 60,000 of Pimlico's capacity of slightly more than 100,000 - a statistic that creates unease about possible muddy conditions and police searches.
"I think people realize we are living in a different world right now, and we are not doing anything different than other sporting events and airports," said Karin De Francis, senior vice president of public relations and marketing for Pimlico. "Our primary concern is the safety and security of the people who will come."
De Francis said there have been no specific threats against the track and no intelligence reports suggesting that an attack is planned.
But experts say a televised event and cultural icon such as the Preakness - which is one of the largest annual gatherings of Americans - is a tempting target. This year's Super Bowl and Salt Lake City Olympic Games drew Secret Service protection after being declared National Special Security Events - a designation that was denied the Kentucky Derby and the Preakness.
Some of Pimlico's security changes will be noticeable. Concrete barriers have been positioned to keep cars and trucks away from the main building. There will be a larger police and National Guard presence than in the past, and some on the perimeter will be armed with semiautomatic rifles.
Fans will be subjected to more thorough searches, possibly with metal detectors, and cars parking in the main lot will be searched. Coolers will not be permitted in the grandstand or clubhouse, though they can be taken to the infield.
De Francis said that the track has received some queries from fans but that most people understand the precautions.
Pimlico, in Northwest Baltimore, generates nearly a third of its annual revenue on Preakness day, so even slight variations in attendance are important.
Churchill Downs, in Louisville, Ky., felt the effects two weeks ago. The Derby suffered its biggest year-to-year decline in attendance in a decade, even though the weather was perfect.
"I think it was the hassle of security more than anything else," said John Asher, vice president of racing communications for Churchill Downs.
The Derby, the Preakness and the Belmont Stakes, which will be run next month in New York, are among the most important thoroughbred racing events and together make up the vaunted Triple Crown.
Churchill Downs drew 145,033 fans for the Derby, about 6 percent less than the previous year but still fifth best in history. Security precautions included a ban on coolers, cans and bottles - and even suntan lotion - and the presence of 1,300 police officers and National Guard troops.
"I didn't think it was too bad," said Chicago financial services manager Kurt Johnson, a Derby veteran who was searched when he entered. "It provided a slight delay, but I wouldn't consider it much of an inconvenience considering the reasons they were doing it."
The track tried to make up for the inconvenience by handing out 250,000 samples of suntan lotion and selling coolers and ice on the infield.
Pimlico has not gone as far with security as Churchill Downs. Fans will be permitted to bring lotion, as well as beverages, including beer and wine, as long as they are in plastic containers or regular-sized cans - no glass.
Coolers, backpacks and thermos containers can be taken to the infield as in past years but will not be allowed in the grandstand or clubhouse areas. In those areas, fans will have to use see-through bags or plastic containers no larger than 18 inches by 18 inches.
Ice and inexpensive coolers will be sold. An extra 24 concession stands will be open.
To ease delays at the gates, the track will open earlier than in the past - at 8 a.m. - and it has added a race at 10:30 a.m. in hopes that people will arrive early.
There is little evidence that the Sept. 11 attacks on New York and Washington have had a long-term effect on attendance at sporting events, said Merrill J. Melnick, co-author of Sport Fans: The Psychology and Social Impact of Spectators.
People often stay home in the days after a national calamity, but gradually return to familiar entertainment rituals, he said.
Baseball attendance nationwide is down 6.5 percent this season. But the just-completed NBA regular season drew 1.1 percent more fans than last season, and the NHL set a single-season attendance record.
Paradoxically, people may find a sense of security in crowds. "There is a certain sense of assurance in numbers. Maybe that and the ritual that is the Preakness is enough to overcome any fears of terrorism," said Melnick, a sociologist at the State University of New York College at Brockport.