WASHINGTON - ACTOR Ashton Kutcher has challenged CNN to an online duel.

The star of the television series 'That '70s Show' and husband of actress Demi Moore is in a race with the 24-hour news channel to see who can be the first to amass one million followers on micro-blogging service Twitter.

Kutcher, whose Twitter handle is @aplusk, threw down the gauntlet to CNN earlier this week after noticing that he had nearly as many followers on his Twitter account as CNN.

'I found it astonishing that one person can actually have as big of a voice online as an entire media company can on Twitter,' the 31-year-old Kutcher said in a video posted to Qik.com explaining his decision to take on CNN.

The actor said that if he reached one million followers ahead of CNN he would 'ding, dong ditch' the house of CNN founder Ted Turner - ring his doorbell and then run away.

Mr Turner does not actually own CNN anymore but the network good-naturedly took up the challenge and taped a video response by talk show host Larry King.

'Hey Kutcher,' King said. 'Are you putting me on? Are you kidding? Do you think you can take on an entire network? 'Do you know how big we are? Do you know what CNN is? Kutcher, you're playing out of your league. CNN will bury you,' King joked.

Kutcher has since promised that if he beats CNN to one million followers he will donate 10,000 mosquito nets to a charity fighting the disease in Africa and give his millionth follower a copy of the videogame 'Guitar Hero.'

Videogame publisher Electronic Arts has also gotten into the act, announcing - on its Twitter feed, of course - that it would put Kutcher's one millionth follower in a Sims videogame and give them all of its 2009 titles for free.

At midnight Singapore time on Thursday, CNN's breaking news feed on Twitter - #cnnbrk - was leading the popularity contest with 966,363 followers to Kutcher's 953,268. -- AFP