Six Flags Over Texas in Arlington, Texas.

Mike Fuentes | Bloomberg | Getty Images

Watch out for the comeback kids. While market records were broken and many stocks surged in the first half of the year, not all of them did.

Wall Street analysts were telling clients there were plenty of values to be found among stocks that ended the first half in the red. CNBC examined the most recent Wall Street research from major firms to find companies that were being recommended as comeback stories to clients after falling during the first six months of the year.

They include names such as Marathon Petroleum, Six Flags, Cigna, TripAdvisor, Pure Storage, and Chemours Company.

Theme park operator Six Flags has been the subject of 3 upgrades over the last month alone with Wells Fargo being the most recent investment bank to lift their rating to buy. The company, which ended the first half down over 10 percent, is due to report earnings on July 24th.

The stock has several “positive catalysts” despite its “volatility,” according to analysts at Wells Fargo.

“We believe concerns surrounding Q219 weather, China trade implications and dividend sustainability, are fairly discounted,” they said.

Health insurer Cigna ended the first half of the year down more than 17%. Shares of the company had been under pressure as the Trump administration was pushing a plan to eliminate drug rebates from government prescription drug plans. But this week the administration dropped the idea.

“We expect the news to be favorable most specifically to entities with larger pharmacy benefit management exposure as it eliminates the uncertainty and overhang that the rebate rule had on those companies,” analysts at Citi said. The firm kept its buy rating and the stock remains on the Citi focus list as a “top pick.”

Travel and restaurant website TripAdvisor finished the first half down 14%. That wasn’t enough to stop analysts at Needham this week from adding the buy-rated company to its “conviction list.”

“We think the setup remains super attractive on a compelling second derivative directional play into 2H19,” they said.

Here’s what else analysts are saying about stocks to watch in the second half: