Campaign group More United – said to have 70,000 members – supported new Lib Dem MP Sarah Olney, who beat Zac Goldsmith

A campaign group led by the historian Dan Snow has crowdfunded £160,000 in two weeks to support progressive, internationalist and pro-EU parliamentary candidates.

The group, More United, was launched after the referendum to support those seeking office who support five principles, including seeking the closest relationship with the EU or rejoining “if that becomes necessary and possible”.

Its name takes inspiration from the maiden speech by the murdered Labour MP Jo Cox, who said people are far more united and have more in common than that which divides us.

However the group, co-founded by the former Liberal Democrat leader Paddy Ashdown, is preparing to back candidates from all political parties that stand up for its aims.

The Crowdfunder platform said the effort was the most successful political campaign to raise money on the site to date, with more than 4,000 backers.

Organisers said More United has about 70,000 members, more than 80% of whom have never been a member of a political party or done any political campaigning.

The first candidate supported by the group was Sarah Olney, the Liberal Democrat who beat Zac Goldsmith in the Richmond byelection this month. Goldsmith, who backed Brexit, resigned as a Conservative to fight a byelection as an independent in protest at the government’s Heathrow policy.

More United said it is aiming to raise £250,000 within the next fortnight, so it can back candidates across the country in byelections.

Snow said he believed More United was an answer for people who are desperate to know what can be done to counter political extremism. “We can organise, raise money, fund progressive candidates, in short, stand up for what we believe,” he said. “Let’s turn our country, once again, into a stronghold for progressive values.

“In Britain, and around the world, politics is being hijacked by extreme views which we believe are not representative of millions of people in this country. It is time for More United, as a tolerant, outward-looking movement, to give people more influence over politics to build a more positive, more united future for Britain.”