The move will allow GM, which is expected today to report second-quarter profits in excess of $1 billion, to begin selling shares before year's end -- possibly by Election Day.

The pre-stock-sale document, known as a registration statement, will reveal GM's business plans and other details of the initial public offering of its stock, known as an IPO.

After its filing, GM executives and its outside advisers will take to the road, meeting with banks and other potential investors about the company's financial prospects in an effort to convince them to buy into the company.

Neither GM nor Treasury Department officials would comment on the filing of its registration statement, which was confirmed by insiders.

"We'll go when the conditions are right and GM is ready," GM spokeswoman Lori Arpin said Wednesday.