Donald Trump greets supporters at a campaign rally in Dallas
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US election: Can Trump 'trump' his US rivals?

Donald Trump is taking on 10 other fellow Republicans with presidential ambitions at a debate in California.

The billionaire is still the front-runner for the Republican nomination, and in recent months he has increased his lead over the other candidates.

The BBC's Jon Sopel looks at the success of the Donald Trump campaign so far.

  • 17 Sep 2015
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