The total is about $3 million less than the amount raised in April by President Obama and the Democratic National Committee, The New York Times reported.
In a statement released Thursday, Romney's campaign reported $61.4 million cash on hand at the end of April. The campaign said 95 percent of the donations last month were no more than $250.
"We are pleased with the strong support we have received from Americans across the country who are looking for new leadership in the White House," Spencer Zwick, Romney's finance chairman, said in the statement.
Romney aides said the total could have been higher if the joint "Victory" fund-raising effort had started sooner. The campaign and the RNC announced they were joining forces April 4 but didn't conduct their first joint event until April 14, the Times said.
"Voters are tired of President Obama's broken promises," RNC Chairman Reince Priebus said in a statement. "Mitt Romney has the record and plan to turn our country around -- that is why he is receiving such enthusiastic support from voters across the country."
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