WASHINGTON (AP) -- Democratic Senator Barack Obama wants to know whether he can take money from donors who want him to be president, then give it back later.

The Federal Election Commission says it will look into it.

Obama is indicating he wants to at least keep the option of using the public financing system for his presidential campaign if he becomes the Democratic nominee. To do that, the Illinois lawmaker couldn't spend any contributions for political purposes, but could instead use federal funding that's expected to total about $85 million dollars for next year's general election.

Obama has decided to raise unlimited private contributions for the primary and general campaigns. So have chief Democratic rivals Senator Hillary Rodham Clinton and John Edwards. Edwards and Obama also say they won't accept money from lobbyists or political action committees.