A senior adviser to Republican presidential candidate Ted Cruz on Sunday accused rival Donald Trump's campaign of taking a "banana republic approach" by complaining that party rules for selecting a nominee are rigged against him.

Former Virginia Attorney General Ken Cuccinelli, the Texas senator's delegate operations manager, said on ABC's "This Week" that the Trump campaign is challenging the delegate selection process "because they're getting beat on the ground."

Cuccinelli and Trump's campaign manager, Corey Lewandowski, as well as the third Republican candidate, Ohio Gov. John Kasich, traded punches over the delegate selection process on Sunday news shows.