Donating blood during a critical national shortage could also send one lucky donor to the Super Bowl.

The American Red Cross says donors who give blood through Jan. 25 will be entered for a chance to win a trip for two to Super Bowl LX in Los Angeles.

The promotion comes as the Red Cross notes that the national blood supply has dropped about 35% over the past month, prompting it to declare a severe blood shortage.

Numerous factors are being blamed for the shortage, including the flu, which the Red Cross says is sidelining potential donors and straining already overburdened hospitals. Severe winter weather in some regions has also disrupted blood drives and donation appointments, further slowing collection efforts.

“This time of year is always challenging for blood collection — but right now, the perfect storm of a long holiday season, record flu activity and winter weather are all impeding donation efforts,” said Dr. Courtney Lawrence, executive medical director for the Red Cross. “Every person’s blood donation can help save lives — plus you help ease the tremendous burden on our doctors and nurses, allowing them to focus on caring for patients.”

The situation is especially dire for blood types O, A negative and B negative, the Red Cross says.

People can schedule an appointment to donate blood through the Red Cross Blood Donor App, visiting RedCrossBlood.org or by calling 1-800-RED CROSS.