Walmart is reportedly planning to debut a $98 annual subscription service called Walmart+ that includes unlimited same-day delivery and discounts at its gas stations. Walmart+ would be a direct competitor to Amazon Prime. And it would cost $21 less per year than Prime.

The Bentonville, Arkansas retailer has spent years and billions on investments in e-commerce in an attempt to leverage its more than 4,700 U.S. stores to challenge Amazon. Walmart+ heats up the showdown between the No. 1 ranked Fortune 500 company (Walmart) and the No. 2 ranked company (Amazon).

Will Americans pay for the new Walmart service? To find out, Fortune and SurveyMonkey polled 2,717 U.S. adults between July 13 and 14.*

The data points to Walmart+ having a strong launch. Among U.S. adults, 27% say they’re likely to subscribe to Walmart’s $98 annual subscription service. That could mean tens of millions of signups.

And Amazon Prime could lose droves of members to Walmart+. Amazon Prime members (31%) are more likely than all U.S. adults (27%) to say they’ll sign up for Walmart+. What’s more, 40% of Prime members who earn under $50,000 say they’d likely sign-up for Walmart+. The jury is still out if they’d subscribe to both services at once. If they switch over, that’d be a massive blow to Prime’s membership base of 150 million.

Americans who shop in store at Walmart are the most likely to say they’ll sign up for Walmart+. The more often they shop in person, the more likely they’ll go online: Among weekly in-store Walmart shoppers, 43% are likely to get Walmart+, compared to 32% of monthly shoppers. (That does beg the question: As Walmart+ grows, would it undercut the company’s in-store sales and traffic?)

As for current online shoppers, 41% of U.S. adults who purchased goods or service from Walmart.com since the onset of the pandemic say they’re likely to subscribe to Walmart+.

This all suggests Walmart+ could quickly build a massive membership base based on existing fans—and maintain that all-important recurring revenue stream.

Amazon Prime members skew towards higher income households, according to this Fortune-SurveyMonkey poll. That makes sense for a company that has strategically worked to cultivate affluent Americans in its base. After all, it purchased Whole Foods.

This might have created an opening for Walmart+ to seize customers on the other end of the spectrum. 33% of U.S. adults earning under $50,000 are likely to sign-up for Walmart+, compared to 23% of $100,000 and above earners.

*Methodology: The Fortune-SurveyMonkey poll was conducted among a national sample of 2,717 adults in the U.S. between July 13-14. This survey’s modeled error estimate is plus or minus 3 percentage points. The findings have been weighted for age, race, sex, education, and geography.

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