It is the largest private US employer, with more than 1.2 million workers, many in the so-called "battleground" states seen as crucial to the success of President George W. Bush or Democratic challenger John Kerry in Tuesday's presidential election.
In 2002, Retail Forward predicted the company would double in size in five years.
More than two-thirds of its stores are in states that voted for Bush in 2000 and the "Wal-Mart" effect clearly leans in favor of the Republicans.
Like some other firms, the company has a political action committee (PAC) to collect donations from employees for campaign contributions.
Wal-Mart's committee was the second most important business PAC in the United States, with nearly 1.5 billion dollars in contributions, about 80 percent of which went to Republicans, according to the independent group Political Money Line.
Wal-Mart has much to gain by supporting candidates who would seek to extend free trade deals with countries like China, a major supplier for the low-cost chain.
Wal-Mart itself has become a political issue for people who blame the company for job and business losses in areas where its discount stores are located.
Vice President Dick Cheney recently defended the company.
"This is one of our nation's great companies, and one of the most familiar names in all of America," he said.
"The story of Wal-Mart exemplifies some of the very best qualities in our country -- hard work, the spirit of enterprise, fair dealing, and integrity," Cheney told Wal-Mart employees in Bentonville, Arkansas, the company's headquarters.
However Wal-Mart has recently been accused of improper behavior with its workers by those concerned over the company's enormous power.
Over the summer, the company was charged with looking into the legal records of some applicants, and at the beginning of the year was caught locking night workers in certain stores.
At the end of last year, hundreds of illegal immigrants were discovered working at Wal-Mart stores, through subcontractors hired for cleaning duties.
"While charging low prices obviously has some consumer benefits, mounting evidence from across the country indicates that these benefits come at a steep price for American workers, US labor laws, and community living standards," Democratic Representative George Miller said in a report earlier this year.
"Wal-Mart's current behavior must not be allowed to set the standards for American labor practices."