President Obama and Mitt Romney have both raised tens of millions of dollars, but they have taken different routes to get there.

A Campaign Finance Institute analysis found that Obama was drawing heavily on donors who contribute small amounts, while Romney is relying on heavyweights who can give more generously. 43 percent of people who contributed to Obama's campaign through April 30th gave less than $200, amounting to about $88.5 million. Those small-time donors comprised just 10 percent of Romney's total, or $9.8 million.

But Romney easily outpaced Obama among donors willing to give the legal maximum of $2,500. 62 percent of the presumptive Republican nominee's donors gave $2,500 versus 16 percent for Obama (those limits do not apply to Super PACs, entities that can raise and spend unlimited amounts of money as long as they don't explicitly coordinate with candidates).

Recently released fundraising numbers show that Romney surpassed Obama in May, combining with the Republican National Committee to pull in $76.8 million. Obama and the Democratic National Committee reaped $60 million.