Former competitors include British rowing legend James Cracknell, who completed the MDS in 2010.

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Stars such as Davina McCall, Alan Shearer, James Cracknell, Tess Daly and Mark Ramprakash are all lending their support to this year's campaign.

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The Australians had proved so strong over the last year that British hopefuls Matthew Pinsent and James Cracknell were moved into the four.

BBC: SPORT | Olympics 2004 | Rowing | Aussies win coxless pairs

Williams, who won Olympic gold in Athens with Matthew Pinsent, James Cracknell and Ed Coode, clinched the 2006 world coxless four title with Reed, Hodge and Alex Partridge.

BBC: SPORT | Other Sport... | Rowing | Hodge and Grainger clinch titles

At the No campaign's rally later, at which Olympic rower James Cracknell, Foreign Secretary William Hague and former Labour minister Lord Boateng will be among speakers, they will argue that AV could embed the Lib Dems in government for generations.

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