"If they all come by car it will be a logistical challenge."

"Let me just say that it's been a logistical challenge," he said.

Immunizing 500,000 health care workers will present huge logistical challenges.

"There obviously were some logistical challenges," he said, "but I think we could have pulled it off."

Because of all the logistical challenges, the official election results are not expected for weeks.

State and local officials say it will be a huge logistical challenge.

But people keep trying, often in the face of daunting logistical challenges.

So this is going to be quite a logistical challenge.

The logistical challenges of making conceptual art can be tremendous.

Despite tremendous logistical challenges, officials hope to finish this second stage in summer.