Several Got Talent acts have had over 1 million views of their auditions on YouTube, while opera duo Charlotte and Jonathan have reached over 10 million worldwide.
Cowell conceded a ratings defeat to Danny Cohen and the BBC last weekend when his own ITV1 series slipped into second spot in the Saturday night ratings war.
However, none of the acts on The Voice UK appear to have captured the imagination of the public like characters on BGT such as Mr Zip (1.5m YouTube views) and Ryan O'Shaughnessy (1.4m YouTube views).
The most-watched Voice act remains teenager Jessica Hammond, who has clocked up 559k in views. Vince Kidd has reached 401k, while one of last weekend's standout acts Bo Bruce has reached only 84k.
The Voice UK continues this Saturday at 7pm on BBC One. Britain's Got Talent airs on Saturday at 8pm on ITV1.
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