Romney wins North Dakota Republican vote

Chicago: Mitt Romney won the North Dakota Republican caucus on Tuesday, scoring a victory over rival John McCain in his bid for the party's US presidential nomination, US media projected.

Romney vowed to press ahead with his campaign for his party's nomination.

"One thing that's clear is this campaign is going on," the former Massachusetts governor told supporters. "It's not all done tonight. We're going to keep on battling."

North Dakota was third state to go for Romney in voting on Super Tuesday, so called because nearly half of the US states are holding contests to choose Republican or Democratic candidates for the November general election.

McCain, an Arizona senator, has won six states in Super Tuesday contests, while former Arkansas Governor Mike Huckabee has won three.