WASHINGTON (AP) – The lone outside group making a concentrated effort to stop Donald Trump from becoming the Republican presidential nominee is circulating a memo in hopes of netting new big donations – or encouraging the four remaining GOP candidates to take on Trump more directly.

Our Principles, a super political action committee that spent $3.5 million on commercials and other voter outreach in Iowa, New Hampshire and South Carolina, on Monday put out the memo titled "Defeating Donald Trump and his Conservatism of Convenience."

Katie Packer, the Republican strategist leading the group wrote in the memo said Tuesday that Our Principles is deciding over whether to attack Trump through a costly national media plan or to target him in key March 1 states.

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