As you've probably heard by now, on Wednesday, Amazon.com (AMZN -1.65%) sent a letter to new U.S. President Joe Biden offering "to assist you in reaching your goal of vaccinating 100 million Americans in the first 100 days of your administration."

On the one hand, the company highlighted its "over 800,000 employees in the United States, most of whom are essential workers" as a great place to start vaccinating. At the same time, with 800,000 workers at its disposal, a vast logistics network, and a host of retail and warehouse properties to work from, Amazon said it was "prepared to move quickly" to help distribute vaccines.

Today, Walmart (WMT 0.57%) raised its hand and declared it could do the same.

Walmart pharmacist inserting a needle in a vaccine bottle.

Image source: Walmart.

The headline of Walmart's blog post from its executive vice president for health and wellness, Dr. Cheryl Pegus, basically said it all: "When Vaccines Roll Out in the U.S., Walmart Stands Ready to Serve."

"Over the past year," says the company, it has been training "thousands of pharmacists and pharmacy techs" at its "more than 5,000 pharmacies in the U.S. and Puerto Rico" to begin administering vaccines. Once vaccines begin arriving, "at full capacity," Walmart says "we expect we will be able to deliver 10-13 million doses per month," running vaccinations "seven days a week at our pharmacies" -- and in particular, in "federally designated medically underserved areas." 

Amazon may be the king of e-tail and package delivery, but "with 150 million people passing through our doors each week," Walmart is reminding the government that it is "in a unique position to reach people where they already shop."  

Investors seem to be betting the government will take Walmart up on its offer. On a down day for the stock market, Walmart stock is up more than 1%.