Mitt Romney and the Republican National Committee raised about $100 million in August, a person briefed on the total said Tuesday.

The nine-figure haul is the Republicans' third $100 million month in a row, putting Mr. Romney on pace to be one of the most successful G.O.P. fund-raisers in history. Most of the money, raised in a series of joint party fund-raisers, will flow to the R.N.C. and other party committees participating in the effort, which can accept far larger checks from individuals than Mr. Romney's own campaign.