Crocs shoes are making a comeback here, and Drew Barrymore could be the reason why

Crocs, the clunky, foam clog that made its debut in 2002, has fallen on hard times of late, but one offbeat indicator may signal better days ahead.

The iconic shoes — which have faced their fair share of criticism for their odd look over the years — are still "flying off the shelves" in the resale market, according to a new report from online consignment shop ThredUp.

Out of 10 struggling retail brands — such as Wet Seal, Ralph Lauren and bebe stores — that were analyzed in ThredUp's e-commerce report , Crocs is the fastest reseller and among the fastest-growing "mall brands" on the thrift shop's website, the company said.

In April, for example, Crocs resold 58 percent faster than the baseline, or average-selling, brands on the website. Nine out of 10 Crocs resell on the consignment shop's website within 18 days, data show.

The brand's new ad campaign, "Come As You Are," which features movie star Drew Barrymore and WWE champion John Cena, may be behind the latest spike, a ThredUp spokeswoman told CNBC, calling it the "Barrymore effect."

It's too soon to say whether the celebrity-driven ad campaign boosted the company's sales as well, but investors will get a better idea on Wednesday when the company reports its earnings before the bell.

Crocs has predicted this year's sales will be flat compared to 2016, as it works to reduce its store count. The company has struggled to reinvent its brand image and appeal to younger shoppers.

Analysts expect the company to report earnings of 3 cents per share on sales of $258.1 million, according to Thomson Reuters' estimates. This compares to Crocs' actual earnings of 7 cents a share on revenue of $279.1 million during the first quarter a year ago.

Earlier this year, Crocs announced plans to reduce its store count by a net 25 percent by the end of 2018, bringing the number of its stores down to 400 over the next two years, from 558 at the end of 2016.

Crocs shares closed Tuesday at $6.20, up 4.2 percent. However, even with this gain the stock has tumbled nearly 20 percent over the past 12 months and is down around 10 percent for the year-to-date period.