But NDP Leader Adrian Dix said the party has done nothing wrong by approaching people who have given the Liberals support in the past.
The Liberals say they have obtained letters sent by the NDP that show the party has specifically approached Liberal supporters to ask for contributions for New Democrats.
The letters request supporters "make a contribution in the range of $5,000 now to show your commitment to a balanced approach to government,” the Liberals state.
Finance Minister Mike de Jong said in a statement the letters amount to "nothing more than a low-down shakedown."
"This is a pressure tactic by the NDP to virtually blackmail businesses across B.C. into donating to their party," de Jong's statement said.
"It is unacceptable, and I am calling on Adrian Dix to accept responsibility for the letters and fire Jan O'Brien, the author of the shakedown letter and the NDP's provincial secretary."
The Liberals declined to release the letters, saying the people who received them do not want to be identified.
At a campaign stop Saturday afternoon, Dix said the NDP has done nothing wrong and he categorically denied his people are trying to strong-arm Liberal supporters into donating to his party, widely considered to be the runaway victor in the May 14 election.
He did not deny that the NDP has approached Liberal supporters.
"The Liberal party raises the vast majority of its money from corporations and certainly, we've sought to raise some and had some success before," Dix said.
"But if anyone is concerned about it I would be happy to talk to them because there is absolutely, absolutely no intent as suggested by the Liberal party or others."
Dix noted he has pledged to end political donations by unions and corporations should he become premier, and urged the Liberals to get behind the idea.
"The reality is we are certainly not demanding anything. We are seeking contributions, as you know, to support the campaign."
When Dix announced his party would end corporate and union donations last week, the Liberals refused to endorse it.
The Liberals are the only major player left in B.C. politics that objects to an outright ban of corporate and union donations, a stance Liberal cabinet minister and spokeswoman Mary Polak attributed to the party's "straightforward'' attitude.
"The reality is, in jurisdictions where you ban union and corporate donations, what you end up with is taxpayers funding political parties,'' Polak said last week. "That's what we've seen federally, and it's what you see commonly in jurisdictions where they make these bans.''
The questions about political donations came on the heels of a cultural and religious celebration attended by the major players of the election campaign.
Vancouver-area politicians added their banners to the sea of colours worn by the thousands of people who are celebrating the Sikh festival of Vaisakhi.
Political party hues of blue, red and green were out in full force on Surrey streets, yet orange was the predominant colour in the exuberant crowd.
While many of the orange turbans worn by South Asians were a religious statement and not a political one, many among the crowd voiced support for the NDP's provincial and federal leaders when they saw Adrian Dix and Thomas Mulcair.
"We regard you, we honour you and we respect you," a Sikh man shouted into a microphone while the NDP representatives made their way through shoulder-to-shoulder crowds.
Bhagat Singh, 49, a taxi driver from Abbotsford, said he'll be voting for change on May 14.
"All parties, same politics. Everybody playing the same game," Singh said, adding he's historically voted NDP and expects to do the same this time around.
Sporting a black toque with green marijuana leaves on it in to mark April 20, another man voiced his desire for an NDP government as Dix exited his greyhound bus.
"Hope you guys win," the man called, on his way to the celebrations.
Dix spent much of the morning greeting voters and making pit stops at union booths and those of his competition.
But Premier Christy Clark says those attending the festivities aren't talking politics, they're celebrating the common values British Columbians share — family, generosity and community.
"Harmony, unity, caring for those who need us, looking out for the underdog, giving, sharing ... weaving us together isn't just something that one or two people do," she said in a speech.
BC Conservative frontrunner John Cummins manned a modest booth early Saturday afternoon, a few stalls down from a stand for Stephen Harper and the federal Tories.
While the BC Conservatives have held fewer campaign events in past week when compared to the dawn-to-dusk efforts by the Liberals and New Democrats, Cummins said his camp plans to ramp up its profile in the weeks to come, starting with events like today's.
"We're optimistic," he said of his party's chances to clinch some seats in Victoria.
Blowing up balloons, Green Party candidate Richard Hosein said he came out hoping to put his party on the map with Surrey voters.
"We have strong connections to the Indo-Canadian community here and we want people to know that we're here to stay," the Surrey-Green Timbers candidate said.
While the party is focusing on a number of ridings on Vancouver Island, Housein said Surrey is not immune to what he called a "holistic" platform that focuses on families and sustainability.
"A lot of people are seeing the Green presence, and a lot of people want change. They kind of see the Greens as the alternative."
Vaisakhi is a holy day in the Sikh religious calendar, celebrated by South Asians with food, live music and dance, fireworks and a parade.
April 20 was also a special day for Dix, who turned 49. NDP staff said they planned to celebrate on the bus, eating a leftover chocolate cake decorated with a Batmobile from the birthday of Dix's chief of staff.
What did the would-be premier want for his birthday?
"The night off, that's pretty good," Dix said, adding it's a gift he'll get as he takes time off the campaign trail tonight to celebrate with his wife.
"It's actually a birthday present for the whole team," he added.
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