Andrew Weaver, whose Green party holds the balance of power, told reporters, "British Columbians were sold a bill of goods on LNG".
Current vote totals put the Liberals with 43 MLAs, the NDP with 41 MLAs and the Green Party with 3 MLAs.
Horgan said he and Weaver agree that the Liberals have failed British Columbians on many issues.
Premier Rachel Notley hasn't commented on the election results so far.
And if not for local NDP riding in-fighting in Cowichan, Columbia River-Revelstoke and Fraser-Nicola over bitterly contested nominations, likely costing the party three seats, Horgan would be premier-elect now. At the outset of the campaign, Weaver made it his mission to expand his party's presence in the legislature, saying that if he was the only Green elected, he wouldn't run again. Or he could simply allow the Liberals to govern as a minority government, in which case the Green vote will become crucial to passing key policies. If there are sufficient absentee votes to change the outcome in either Courtenay/Comox or Maple Ridge/Mission, the Liberals could obtain the 44 seats necessary for a majority.
The Liberals accused the NDP of failing to explain how they would pay for their campaign promises.
The results aren't 100% official, however, as the final count, which includes absentee votes, are tallied between May 22nd and May 24th.
Christy Clark has been premier since February 2011 when she won the Liberal leadership race to replace former premier Gordon Campbell.
The ridings that need to be checked are Courtenay-Comox, where the BC NDP candidate won by only nine votes and Maple Ridge-Mission where there's a difference of 120 votes.
"We inspire people to vote for something... and those people are from across the political spectrum", Weaver said.
In the run up to the election, Weaver said that he had three make or break issues when it came to propping up a party in power, including ending corporate and union donations, a referendum on some form proportional representation, and a significant increase in education funding.
Almost 8,600 students at more than 50 local public schools, private schools and alternate education sites cast ballots and returned NDP candidates in all four ridings.
"He's a smart, thoughtful, reasonable guy, and so we've found places where we can work together".
NDP Leader John Horgan held a news conference shortly after, where he revealed his intention to take the reins if the final count goes in his party's favour.
"The big win for the Green Party is electoral reform because small parties like the Greens are forever disadvantaged by a first-past-the-post system".
"Voters know best. And they reminded us tonight that we are far from ideal", Clark said.
"This is truly historic", she said.
Weaver said he called both leaders to congratulate them.
Neither the NDP nor the BC Liberals can yet confidently claim victory with the two parties near deadlocked in the seat count and a minority government now expected.
NDP Leader John Horgan opposes Kinder Morgan's C$7.4 billion ($5.4 billion) Trans Mountain oil pipeline expansion and has also expressed reservations about the $27 billion Pacific Northwest liquefied natural gas terminal that Malaysia's Petronas wants to build.