More major area retailers are opening their stores on Thanksgiving Day in a quest to snag more of the bounty brought by holiday shoppers.

The holiday openings reflect a game of one-upmanship as retailers scramble to get as big a piece of the holiday shopping pie as they can. And it’s a big pie: Last year, day-after-Thanksgiving sales rose 6.6 percent to $11.4 billion, according to the Chicago-based research firm ShopperTrak – the largest single shopping day of the year.

Attempts to extend the already-lengthy Thanksgiving-to-Christmas shopping season by a few more precious hours illustrate just how much competitive pressure retailers are facing to achieve their 2012 sales goals and “to turn red ink into black ink,” said Serdar Durmusoglu, assistant professor of marketing at the University of Dayton.

For that reason, the day after Thanksgiving has become known as Black Friday.

Durmusoglu said retailers are being especially aggressive because this year is a presidential election year; one recent survey showed that as many as one in five Ohioans may postpone their holiday shopping until after the election, narrowing the window for retailers to ring up sales.

Sears announced that its stores will open at 8 p.m. Thursday and stay open all night, straight through to 10 p.m. on Black Friday. Kmart, also owned by Sears’ parent company, will be open from 6 a.m. to 4 p.m. Thanksgiving Day, then will reopen at 8 p.m. Thanksgiving evening until 3 a.m. And Old Navy stores will open its local stores from 9 a.m. to 8 p.m. on Thanksgiving Day.

Sears officials said the decision to open on Thanksgiving Day is in part a response to feedback that customers wanted to see more flexible Black Friday hours and were also eager to shop a variety of “doorbuster” deals.

But Sears officials also appeared sensitive to a potential backlash to their decision to encroach upon a tradition-steeped, family-focused holiday. Other retailers have felt some heat for expanding their hours on or around the holiday.

A petition on change.org encourages Old Navy to close on Thanksgiving Day so that employees can spend time with their families, and last year, a part-time Target employee launched a petition on the same website seeking to reverse Target’s decision to open at midnight on Thanksgiving night.

“We understand that many of our associates want to spend time with their families on the holiday, so Sears and Kmart will staff its stores with seasonal associates and those who have volunteered to work on Thanksgiving Day,” Ron Boire, executive vice president and chief merchandising officer for Sears and Kmart, said in a news release. Both Sears and Kmart will be closed on Christmas Day, Sears officials noted.

Many retailers that operate out of free-standing stores have not yet announced their holiday hours. Last year, Walmart opened at 10 p.m. on Thanksgiving evening, and Target was among the large number of retailers that pushed back their Black Friday opening bell to midnight Thanksgiving night.

The Dayton Mall, which will have one entrance open Thanksgiving Day to accommodate its Old Navy store inside the mall, will open all of its doors at midnight, according to its general manager, Dave Duebber.

“I would imagine that at least 75 percent or more of our stores will be taking advantage of the midnight opening opportunity,” Duebber said.”Based on last year, we are anticipating very heavy traffic from midnight through about 7 a.m., as many stores will be running their ‘doorbuster’ specials throughout the night and early morning hours.”

The Mall at Fairfield Commons in Beavercreek will open at midnight, and has more than 50 tenants — retail shops and restaurants — prepared to open the moment that Black Friday begins.

Steve Willshaw, general manager of The Greene in Beavercreek, said a number of stores, including its Old Navy location, will be open Thanksgiving Day. Four restaurants will all be open on the holiday as well. At least 20 retailers will open at midnight , and another half-dozen will open as early as 4 a.m., Willshaw said.

Officials at the Towne Mall in Middletown discovered Wednesday that its Sears anchor store will open at 8 p.m. on Thanksgiving, and after checking with some of its other tenants, decided to go ahead and open up the mall at 8 p.m., according to Trisha Hale, Towne Hall’s general manager. Hale said she anticipates at least some other smaller retailers to open Thanksgiving night, and at least two of the mall’s other anchor stores, Elder-Beerman and Dunham’s Sports, are tentatively planning to open at midnight Thursday night.

The Upper Valley Mall near Springfield will open its entrance to accommodate its Old Navy store’s Thanksgiving hours, then will open mall-wide at midnight Thanksgiving night and stay open until 10 p.m. Friday, according to Carla Miller, the mall’s director of marketing and business development.

Town & Country Shopping Center in Kettering, which is normally closed on Thanksgiving Day, will open its front center entrance only at 10 p.m. on Thanksgiving evening to accommodate its Jos. A. Bank men’s clothing store, which will open at 10 p.m. on the holiday and close at 2 a.m. Friday morning, according to Pamela Cochran, Town & Country’s property manager. The shopping center will then reopen at 5 a.m. or 6 a.m. for a full day of Black Friday shopping.

A spokeswoman for the Miami Valley Centre Mall said the Piqua retail complex is planning to open at midnight on Thanksgiving.