A new poll has found that more than half of US voters believe the systems for choosing presidential candidates is "rigged", Reuters reports. In addition, more than two out of three want the system to be changed.
The poll was carried out by Reuters and Ipsos, and reflects frequently complaints by candidates Donald Trump and Bernie Sanders that they are being held back unfairly.
The two party choose their candidates by a complex combination of primaries, caucuses and conventions. Each state works differently, and allow the general public varying levels of participation.