Could there be doughnuts in Carl’s Jr.’s future?

That was some of the speculation last week after the surprise announcement that CKE Restaurants Inc., the parent of the fast-food burger chain, had agreed to be acquired by Thomas H. Lee Partners, a Boston private equity firm best known for taking Dunkin’ Donuts private in 2005.

Some sort of cross-marketing move perhaps.

And why the surprise? It’s partly because of the Carpinteria company’s recent losing position in the so-called “burger wars.”

After years of riding high on its premium Six Dollar Burger menu – sold in sexy ads featuring scantily clad Paris Hilton – CKE has been pummeled as McDonald’s and other competitors have added recession-busting “dollar” and value meals.

The relative performance of the two companies was reflected in the latest quarterly figures, when same-store sales were up 2.6 percent for McDonald’s and down 2.6 percent for CKE. It’s also been reflected in CKE’s stock, which in mid-2007 was trading at more than $22 a share, but for months has languished at less than $9.

“It’s surprising in the sense of the timing,” said Tony Brenner, a senior analyst with Roth Capital Partners in Newport Beach. “It’s happening at a time when CKE results are somewhat depressed; their sales performance is not attractive at the moment – and yet the economy appears to be beginning to recover.”

However, others believe that depressed stock price is likely why the private equity firm agreed to pay $928 million in cash, or about $11.05 per share, for CKE, which operates 1,221 Carl’s Jr. restaurants and 1,913 Hardee’s sister restaurants in the U.S. and overseas. The offer represented a 24 percent premium on the $8.60 per share closing price the day before the offer was made. Shares closed at $11.18 on March 4.

Indeed, in a not-so-subtle indication that the offer is a relative bargain, the agreement includes an unusual provision that allows CKE to “actively solicit superior proposals from third parties” for a 40-day period ending April 6.

Conrad Lyon, an analyst for Global Hunter Securities in Newport Beach, characterized the pending deal as “more of an opportunistic type of event” for the private equity firm, as it seized on the deflated stock price.

Lyon said Carl’s Jr. has been hit especially hard by high unemployment – particularly among teenage males who are its primary customers in California – and a steadfast refusal to lower prices.

“Most people who frequent fast-food joints tend to be the younger crowd, maybe 18 to 34,” he said. “There’s no question that unemployment has been a big issue for them. Throw in the burger wars, and the effect has been huge.”

But with the economy in recovery mode, Lyon said there is really no reason to expect sales will not pick up at Carl’s Jr. “If your time frame is in excess of five years, it could be argued that Thomas H. Lee got a good price.”

Neither CKE nor Thomas H. Lee Partners would comment on the pending deal. In statements released Feb. 26, however, both companies gave it praise.

“We believe this transaction provides excellent value to our shareholders and represents an exciting opportunity to continue the growth and development of CKE restaurants with THL,” said CKE Chief Executive Andrew Puzder.

Todd Abbrecht, managing director of Thomas H. Lee Partners, hinted in his statement that Puzder – who has been credited with the development of the Six Dollar Burger concept and the notable turnaround of Carl’s Jr. over the last decade – would stay on.

“THL is pleased to partner with CKE’s seasoned management team to continue building on the company’s powerful brands and strong position in the marketplace,” Abbrecht said.

However, even though CKE management has refused to match competitors by lowering prices or promoting value meals, Lyon said he wouldn’t be surprised if the new ownership required management to take those steps.

In addition, he said, there could be some cross-branding to leverage income and costs. Analysts note Lee has turned around Dunkin’ Donuts from a tired old chain into a winner.

“It could be lots of fun,” the analyst said. “I personally will be watching to see if they start selling doughnuts.”