The Conservative Party are reportedly spending more than £100,000 a month on Facebook in a bid to promote their content on the social media site and help get David Cameron re-elected.

The Tories were charged £122,814 ($186,727, €164,149) in September last year, while another invoice shows they spent over £114,000 in November, the BBC reported.

The figures come with less than 100 days before the general election and as the UK political parties ramp up their campaigning.

"The Conservatives are spending their money in a way that gets their content in front of people," Matthew McGregor, a former new media adviser to Barack Obama, told the BBC's Today programme.

"The fact they are outspending the Labour Party many, many times over because of the support from millionaire donors is going to have an impact.

"That's something the Labour Party can respond to by out-organising the Conservatives."

But figures last month revealed that Ukip was the most talked about major political party on social media.

We Are Social found that 30% share of the political conversation on Twitter in the three months to January.

Labour had 29% on the site, 25% for the Tories and 11% for the Scottish National Party (SNP).

On Facebook, Ukip was the fastest growing party (8% growth), followed by the Greens (7%) and the Tories, with the SNP on 5%, Labour 4% and the Liberal Democrats on 3%.

"There really is no stand-out party on social media at the moment; all parties could be using social media to communicate and engage in much deeper ways with voters," said Paul Greenwood, a senior research director at We Are Social.

"Current Twitter conversation volumes show that UKIP has stolen a march on the larger parties, partly due to having their first two MPs elected to Parliament in that timeframe.

"Across its social channels, UKIP looks to be a strong challenger brand, getting its tone of voice right for its audience."

He added: "However, looking at this in a more holistic manner, Labour seems more at home than most other parties on Twitter, with a consistent tone of voice and wide reach, talking about the issues that matter to the public.

"However, using this as a prediction for any kind of result at the election is dangerous at this stage, especially given that most social media predictions were dramatically wrong about the Scottish Referendum."

The Conservatives had not responded to a request for comment at the time of publication.