The 4th GOP debate

Republican White House hopefuls John Kasich, Jeb Bush, Marco Rubio, Donald Trump, Ben Carson, Ted Cruz, Carly Fiorina and Rand Paul struggled to break away from the pack in an election debate with fewer personal barbs but some feisty exchanges on immigration and national security. The eight top candidates gathered in Milwaukee for a forum that distilled their differences in substance and style but did little to dramatically change the contours of the race.

Low-pollers Chris Christie and Mike Huckabee, however, failed to make the cut. They were relegated to an undercard debate that was held prior to the main event and which also featured Louisiana Gov. Bobby Jindal and former Pennsylvania Sen. Rick Santorum. (AFP)

Here are highlights from the fourth official Republican presidential debate.

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