General Motors plans to start trading shares again on Nov. 18, timing that allows the company one more quarter of earnings to build its case to investors, a firm that researches initial public offerings told The Associated Press.

Scott Sweet, the managing partner of IPO Boutique, said GM plans to price the shares on Nov. 17 and begin selling them the next day. He said the automaker wants to start a two-week a road show to drum up investor interest on Nov. 3, the day after the midterm congressional elections.

It's unclear if the IPO dates have been finalized. Two people with knowledge of the process say the automaker's board hasn't approved a date for the IPO but is expected to meet next week to discuss the issue. GM is in a "quiet period" before an IPO, so no one is authorized to discuss the process publicly.

The company filed paperwork for an initial public offering with federal regulators last month. GM spokeswoman Renee Rashid-Merem declined to comment Thursday on the timing of the IPO.

Sweet said his information comes from multiple people on Wall Street but declined to name them. He says the company hasn't yet established a price for the shares, but hopes to raise $15 to $20 billion with the initial public offering.

The timing could disappoint some Democrats who supported the government's $50 billion bailout of GM last year and wanted to point to a successful IPO before the elections. But one more quarter of earnings could help the automaker establish that it is healthy and capable of making sustained profits. GM earned $2.2 billion in the first half of 2010 despite depressed U.S. auto sales, but it lost $3.4 billion in the fourth quarter of last year.

GM also hopes the U.S. auto market sees some modest improvement this fall. On Wednesday it said its U.S. sales fell 5 percent from July and 11 percent from last August, when they were boosted by the Cash for Clunkers program.

Dan Akerson, who became GM's CEO on Wednesday, didn't mention the IPO in his first e-mail to employees Thursday. Akerson wished employees a happy Labor Day weekend and said he has already met with United Auto Workers President Bob King. Akerson said he is "from a union family" and believes "very deeply" in working together with the union.

"There will always be more hard work ahead of us, but because of your dedication, I have great optimism for GM's future," Akerson said in the e-mail obtained by The Associated Press.

Akerson took over from Ed Whitacre, who has resigned as CEO but will remain chairman of GM through the end of this year. Both men are former telecommunications executives appointed to GM's board by the federal government.