Donald Trump and another GOP Presidential candidate are swapping insults.

FOX News Radio's Rachel Sutherland reports from Washington.

South Carolina Senator Lindsey Graham says he may be getting a new cell phone now... after Donald Trump gave out his phone number to the world and encouraged people to call. Here's Trump on the stump in South Carolina yesterday .

(Trump) "I see your Senator, what a stiff, what a stiff, Lindsey Graham."

There were plenty of insults to go around. Trump also made fun of Rick Perry's glasses and said Jeb Bush is weak on immigration. In a statement, Graham's campaign manager said Trump "continues to show hourly that he is ill-prepared to be commander-in-chief".

Rachel Sutherland, FOX News Radio.