The Illinois Democrat made his comments during a stop today in Indianapolis.
Obama has raised a whopping $234 million from about 1.3 million donors.
But he says the limited amounts of money available from the federal treasury for presidential campaigns pose difficult choices for candidates raising large sums.
Obama earlier likened his fund-raising to a "parallel public financing system." That remark set off speculation that -- if he's the Democratic nominee -- he would be the first presidential candidate to forgo federal funds in three decades.
But Obama today said he hasn't made a decision about his general election money plans.