US-style political attack ads have quietly come to the UK, thanks to the Conservatives using a loophole in election rules to target voters by using paid-for YouTube ads.
YouTube viewers in marginal constituencies told BuzzFeed News they have recently begun seeing paid-for "pre-roll" adverts from the Conservatives attacking Ed Miliband and linking him to Alex Salmond and Gerry Adams.
The new campaign tactic, a first in UK politics, enables the Tories to completely bypass Britain's strict ban on paid-for political TV adverts and allows the party substantially more freedom to target video adverts at individuals in marginal constituencies.
What's more, unlike expensively produced political party broadcasts which are shown in carefully allocated slots on national TV channels, this form of YouTube advertising could enable the Conservatives to produce fast-turnaround negative attack adverts within hours based on recent events.
The party can then pay for these to be pushed out to hundreds of thousands of individual voters using the video-sharing site. This gives the Conservatives a massive campaigning advantage over their rivals and allows them to reach potential voters who do not read newspapers or watch TV.
While the UK's political parties have been uploading clips to YouTube for years in the hope they go viral of their own accord, the Conservatives appear to have taken the game-changing decision to spend substantial sums of money actively putting them in front of viewers.
In 2013 the courts narrowly upheld the continued ban on political advertising on British TV but the growth of online video advertising risks making this decision irrelevant.
YouTube's ability to micro-target adverts by age, gender, and location means the the party can also ensure they only show paid-for videos to likely voters in marginal constituencies.
For example, using Google's demographic data it is simple for the Tories to target males who are aged over 45 and have children.
This can then be refined to only target men who are concerned about politics, jobs, and their houses.
What's more, the Conservatives can even target the ads by postcode to ensure that viewers in different parts of the same constituency see different ads.
Jim Waterson is a politics editor for BuzzFeed News and is based in London.
Contact Jim Waterson at firstname.lastname@example.org.
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