Digg is working with CNN’s citizen journalism site iReport to allow users of the social bookmarking site to pose questions to members of the Democrat and Republican conventions taking place in the US over the next two weeks.

The Digg Dialogg feature, which will be used for the first time at the conventions, lets users submit text or video questions to be put to a particular interviewee. These are then ranked by other Digg users with the top 10 posed to the subject during a live interview.

The first candidate will be Nancy Pelosi, speaker of the US Democrats’ House of Representatives, said Kevin Rose, founder of Digg, in a blog post.

According to a release from CNN, the news organisation broke the one billion barrier for page views on its politics site, which was launched last September; while its blog, the CNN Political Ticker, recorded its highest ever traffic on August 22 with more than 2.7 milion page views – driven by the announcement of presidential candidate Barack Obama’s running mate.