UPDATE 3-UK PM Johnson's party raises 26 times more in donations than Labour

* Conservatives raised 5.7 mln pounds in 6 days

* Labour raised 218,500 pounds

* Figures collated by the Electoral Commission (Adds details)

By Kate Holton and Andrew MacAskill

LONDON, Nov 21 (Reuters) - Prime Minister Boris Johnson's Conservative Party raised 26 times more in political donations than the main opposition Labour Party in the first week of the official British election campaign.

The Conservatives raised 5.7 million pounds ($7.4 million) in six days from Nov. 6 while Jeremy Corbyn's Labour raised just 218,500 pounds ahead of the Dec. 12 vote, the Electoral Commission said.

Of all the donations made to the political parties in the period, 87% went to the Conservatives.

Johnson’s ability to pull in such large donations underlines his popularity and boosts his party, which is already ahead in the polls. But it could also help Labour renew its charge that the Conservatives are home to billionaires, bankers and big business.

Labour even trailed two of the smaller parties in the fundraising stakes, although it tends to raise more money from smaller donations that fall below the Electoral Commission's 7,500-pound notification threshold.

"While the Conservative Party is in the pockets of vested interests and the super-rich, we are proud that the Labour Party is funded by hundreds of thousands of people donating what they can afford to build a fairer society," Labour Chairman Ian Lavery said in response to the figures.

The biggest Conservative backer was John Gore, a developer, producer and distributor of Broadway theatre, who gave 1 million pounds.

The next three largest were the travel company Trailfinders, Countrywide Developers and WA Capital, who each gave 500,000 pounds to the party.

The party also received 200,000 pounds from Lubov Chernukhin, the wife of a former Russian minister, the Electoral Commission said. Howard Shore of Shore Capital donated 250,000 pounds and hedge fund manager Andrew Law gave 200,000 pounds.

Labour's biggest donation came from the Unite union.

Separately the party's left-wing campaigning arm Momentum said it had raised over 450,000 pounds since the start of the campaign, made up of small donations.

Labour also boasts many more members than the Conservatives who can help campaign door-to-door in the run-up to the vote.

For the smaller parties, the pro-EU Liberal Democrats raised 275,000 pounds as a whole in the Nov 6-12 period. Nigel Farage's Brexit Party raised 250,000 pounds from a single donation from businessman Jeremy Hosking.

At the end of last year, the Conservatives posted their first deficit in eight years and were in a worse financial position than Labour, according to annual accounts published in August.

However the party raised more than Labour earlier this year as it became apparent that Britain was set to hold another election, while Johnson himself broke the record for the most money raised by a British politician in his bid to become prime minister earlier this year. (Editing by Stephen Addison)