Retailers are scrambling to fill the void left behind by Toys R Us by convincing shoppers their stores are the go-to place to find toys this holiday season.

The biggest winners so far appear to be Walmart and Target, according to a study by Gordon Haskett Research Advisors in partnership with data provider Alpha Hat. They surveyed more than 50,000 people who had shopped Toys R Us in July of last year and then shopped another retailer after Toys R Us' stores were all closed, in July 2018, noting where those people chose to go otherwise.

Walmart has been the biggest winner so far and captured 26 percent of lost Toys R Us traffic, Gordon Haskett said in a research note. Target got 14 percent, while dollar stores including Dollar General and Dollar Tree captured 10 percent, and Costco 8 percent.

Together, those three retailers and the category "dollar stores" captured roughly 58 percent of traffic that used to funnel to Toys R Us stores. To other retail analysts, this should offer a good picture of where consumers are planning to head this holiday season.

"Recent commentary from retailers suggest that companies will be shifting spend to increase their respective toy offerings and/or augment the presentation of products in light of over $1.0 billion of share up for grabs post the Toys R' Us closings earlier this summer," Gordon Haskett analyst Chuck Grom said.

While Costco isn't typically known for having a large toy selection, the study said the company saw the biggest increase — even more than Walmart — year-over-year in traffic from shoppers who used to go to Toys R Us but now go to the wholesaler. It had 18 percent more visits this past July than it did a year prior from former Toys R Us shoppers. Costco could talk more about the holidays when it reports earnings on Oct. 4.

Walmart has already said it will have 30 percent more toys in stores later this year. Target said it will roll out more than 2,500 new and exclusive toys in the coming months.

Kohl's has said it will bring in new brands FAO Schwartz and Lego ahead of the holidays, while J.C. Penney has also promised to bulk up its toy assortment, particularly items for babies, trying to capture market share left behind from Babies R Us.