By Nicole Mordant
VANCOUVER (Reuters) - British Columbia's ruling Liberal Party and the opposition New Democratic Party were in a dead heat as election campaigning kicked off in the western Canadian province on Tuesday, four weeks before voters go to the polls.
A loss for the Liberals on May 9 could derail big oil and gas projects in the province. NDP leader John Horgan has vowed to stop Kinder Morgan's Trans Mountain pipeline expansion and has expressed reservations about a liquefied natural gas terminal that Malaysia's Petronas [PETR.UL] may build.
The Liberals are seeking a fifth consecutive term, with a backdrop of voters opting for change in the neighboring province of Alberta in the Canadian federal election and in the United States in the past two years.
The provincial Liberals are not linked to Canadian Prime Minister Justin Trudeau's Liberal Party and are more right-leaning.
Adding uncertainty to the outcome of the provincial election is an early jump in support for the BC Green Party and its leader, Andrew Weaver, said David Valentin, executive vice president at Ottawa-based polling firm Mainstreet Research.
Although support is up, nearly half of Green Party supporters say they might change their minds about which party to give their votes. It is not clear which of the two big parties would benefit the most.
"That is the X-factor for us right now because we have seen so many elections where the improbable becomes not just probable but reality," Valentin said in an interview.
He pointed to the surprise win in 2015 by the left-leaning NDP in the oil-producing province of Alberta, a traditional Conservative Party stronghold.
According to the latest Mainstreet/Postmedia poll, which surveyed respondents April 1-3, 26 percent of voters would back the Liberals, 29 percent the NDP, the official opposition, 13 percent the Green Party and 9 percent the Conservative Party. Some 23 percent of voters were undecided.
The issue of fundraising is expected to emerge as a campaign issue in a province that has few limits on political contributions. The New York Times in January called British Columbia the "'Wild West' of Canadian political cash" and said there was an "unabashedly cozy relationship between private interests and government officials in the province."
Unaffordable housing could also weigh on the Liberals, who have been in power for nearly 16 years. With its million-dollar tear-downs, Vancouver, British Columbia's biggest city, is the most expensive real estate market in Canada.
(Reporting by Nicole Mordant in Vancouver; Editing by Dan Grebler)