Yes, I believe betting syndicates played a major part in Helen's win.
She was 60/1 for most of the series, and still 33/1 in the week leading to the final week.
Those were ridiculous odds for someone with a pass to the final.
She was still 25/1 when "Finalist" appeared under her name on the board.
Her odds then started to tumble, and were down to 3/1 on final day.
For odds to tumble in such a manner means that lots of (large) bets were placed on Helen to win.
People who placed bets on her when she was between 60/1 and 25/1 would've made a killing.
Place £1k at 33/1, spend 2k voting over different methods (payphone, landline, mobile, app), get £34k back.
A few syndicates with 10-50 members each doing this, and you soon have your 4k votes difference that got Helen the win.
Ashleigh's voters were conned into believing she was going to win easily (odds were virtually at evens, topping all the polls comfortably, etc) so maybe they didn't feel the need to vote as passionately.
Sure, I'm not saying that Helen didn't have any genuine support as well, but I believe those ridiculous odds were always going to attract gamblers, and that they made all the difference.
[edit]
Re: CLL Dodge's post above
Yup, I agree. I also think there could be insider collusion involved here.
Originally Posted by dialectic:
“BIB : She is now saying that she was bothered in the house with Pav staring at her and that she was glad Chris said something about it. IMO it is her fault that Chris got involved to defend 'Princess Ashleigh' from 'stares'. Chris fans should be fuming.”
I disagree. It's BB/Endemols's fault for misleading the viewers with their editing.