WASHINGTON — Donors who backed Republican rivals of presidential candidate Mitt Romney appear to be slow coming to his aid.

Romney raised more than $40 million last month as he solidified his chances of being the GOP nominee. Yet an Associated Press review of new financial data finds only a handful of his recent contributions came from donors to his former primary challengers.

Among the tens of thousands of donors who wrote checks for former candidates like Newt Gingrich or Rick Santorum, roughly 500 contributed last month to Romney's White House run.

Romney began raising money last month with the Republican Party as he looks to unseat President Barack Obama in November. He has been courting the conservative base of his party with media appearances and speeches.

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