The former president was campaigning for Pennsylvania candidates Doug Mastriano and Mehmet Oz when he mocked his onetime ally.
“We’re winning big, big, big in the Republican Party for the nomination like nobody’s ever seen before,” Mr Trump claimed while discussing his standing in the polls.
“There it is, Trump at 71, Ron DeSanctimonious at 10 per cent.”
His comments drew little reaction from the crowd.
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