With Amazon’s Prime Day expected to do more volume than a year ago, retailers are again taking notice and counterpunching with their own version of summer deals.

Many retailers last year competed with Prime Day by having their own sales on the same day. That timetable has shifted this year, with some beginning their sales events as early as last week and others holding the events longer than just the one day, with some running through to the end of this week.

J.C. Penney began its special promotions on Monday, and will continue with them through Tuesday. Dubbed “Penney Palooza,” the specials include free shipping for orders over $49.

Bon-Ton Stores held a Cyber Monday sales day, although the sales were available in the stores as well. E-mails were sent to customers noting a promotional code to receive free shipping on orders $25 and over. It also provided an additional $25 off on purchases over $75 with a special code. The retailer offered door busters for selected products: 40 percent off shorts from Silver Jeans Co.; up to 50 percent off sunglasses from Steve Madden and Relativity; 50 percent off sandals from Anne Klein, Bandolino and Madden Girl, and 50 percent off golf apparel from Izod Golf, PGA Tour and Chaps. Further, the retailer was offering yellow dot clearance savings of up to 80 percent off when using a third promotional code.

Wal-Mart Stores Inc. promised free shipping for five days, without any minimum purchase requirement. It is planning special discounts, mostly on electronics such as a 55-inch Samsung 4K Ultra HD TV discounted to $598 from $1,199. It is also offering a free 30-day test of its new $49-a-year ShippingPass Service, a new option to rival Amazon’s two-day Prime service.

On the specialty store side, many chains were offering its own selection of store sales. In addition to sales of up to 60 percent off certain items, The Gap was taking 40 percent off online purchases on Monday for consumers using the coupon code SUN, while Banana Republic, which began its sales deals last week, took an additional 50 percent select items purchased through Monday. Consumers on Monday who used the promotional code TODAY were able to receive 60 percent off select styles.

Online site ebags.com said last week it would piggy-back Amazon on Prime Day, participating in the selling event and on the same day holding a special back-to-school season on its own site. The e-tailer said it plans to offer discounts up to 85 percent on a limited time on the extreme deals section of its site.

“In preparation for summer’s biggest shopping day, eBags has negotiated unprecedented savings with some of their most popular brand partners, including Delsey, Kenneth Cole Reaction, Travelers Choice, Samsonite and more,” eBags said.

EBags also said that in addition to special reward points for its members, its social team will also showcase popular eBags brand products with Facebook Live giveaways every hour throughout the workday, as well as chances for followers to win select items such as a Lifeboat quick-charge portable battery and a Savvy laptop tote.

And Jet.com will hold a one-year anniversary sale. The company launched a week after Amazon held its Prime Day last year.

While many sites are providing special sales, they’re also not referring to them as Prime sales as they do for Black Friday or Cyber Monday so as not to draw any additional attention to Amazon’s sale event. That made it hard sometimes to tell whether discounts were being ramped up to compete with the web behemoth.

Talbots has been holding its semiannual sales event, and over the weekend boosted the discount to up to 60 percent off original prices. On Monday morning, it sent e-mails out stating that the discount has been upped to up to 70 percent off.

J.P. Morgan internet analyst Doug Anmuth said Prime is fueling Amazon’s flywheel and is a major driver of growth because it has become an important Prime customer acquisition event. Prime Day is available only to Amazon’s Prime members, although nonmembers can partake by signing up for a trial membership. Anmuth said “hundreds of thousands of new members trialed the service on Prime Day 2015.” The analyst said that while some will not convert to paying subscriptions, many others will and Amazon captures them before the holiday sales period starts. He also projected that Prime members “spent 3x to 6x as much as regular Amazon buyers.”

Data analytics firm DynamicAction said that the Prime wallet online is getting bigger by more than 30 percent each year. That leaves retailers fighting for a smaller share of the online wallet, and the only way they can compete is by getting promotional. But whether they can really compete is debatable.

According to data from J.P. Morgan, 34.4 million items were ordered at last year’s Prime Day, or 398 per second, which broke all prior Black Friday records. And while Anmuth said many retailers will try to compete through similar sales this year, he also concluded that “Prime creates a higher bar for online retail and operates with a scale and feature set that can’t be replicated.”