British Columbia's premier visited the province's lieutenant-governor on Tuesday to officially launch the campaign for the May 9 vote, setting off a four-week fight in which messages about affordability and the economy will compete with what are expected to be nasty attacks between party leaders.

Read more: B.C. parties roll out platforms ahead of campaign

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Read more: With campaign set to begin, B.C.'s parties prepare for a ground war

Here's what you need to know about the campaign, who's running, and what issues are likely to factor into the outcome:

The campaign

B.C.'s fixed election dates mean the timing of the vote is no surprise, and the two main parties have been in campaign mode for quite a while. Both parties have been running ads for months, including sharp attacks on each other's leaders, and the Liberals, NDP and third-place Greens all launched their campaign buses and began rolling out platform promises in the week leading up to the writ drop.

What changed on Tuesday is that campaign spending limits and other rules about election advertising took effect. Parties can spend a maximum of $4.4-million, while individual candidates are capped at $70,000.

When it comes to reaching those limits, the Liberals are in considerably better shape than the NDP. The Liberals raised $13.1-million in 2016, mostly from corporations and other business donors, and have already raised more than $4-million in 2017 alone. The New Democrats, in contrast, raised $6.2-million last year.

Another difference this year is that the electoral map has been redrawn since the last election, with two new ridings bringing the total number to 87. An analysis of the 2013 results transposed onto the new boundaries doesn't change the landscape much, with the Liberals and the NDP ending up with an extra seat each.

The same analysis identifies 14 ridings with margins of victory of less than five per cent, mostly in the Vancouver region.

The parties

The BC Liberal Party, a centre-right coalition that is not affiliated with the federal Liberals, has been in power since 2001, with Christy Clark as premier and leader for the past six years.

In her first campaign as leader in 2013, Ms. Clark pulled off a remarkable upset, holding onto power despite numerous polls that predicted an NDP landslide.

Back then, Ms. Clark was a fresh face who was able to distance herself from the perceived failings of her predecessor, Gordon Campbell, while also promising a rich future built on liquefied natural gas. In the years since, the LNG industry has yet to materialize and Ms. Clark's government has accumulated its own share of scandals and controversies. Those include the mass firing of health researchers, including one who killed himself; several high profile cases of children dying in government care; welfare rates that have not increased in a decade; allegations bureaucrats were deleting records to shield them from public view; a breach of trust charge against a government communications staffer; skyrocketing real estate prices that have fuelled a housing crisis; and a refusal to rein in the influence of corporate money in politics, among others.

The New Democrats are campaigning with their third leader in as many elections. John Horgan had been in the legislature for nearly a decade when he was elected party leader in 2014, though many British Columbians likely do not know much about him. The party will spend much of the campaign introducing Mr. Horgan to voters while fending off Liberal attacks (which have already begun) that Mr. Horgan is a weak, inconsistent leader who can't be trusted with the province's economy.

The NDP would need to win an additional 10 seats to win a majority, and while their support has grown since the rout of 2001, the party has not won the popular vote in 26 years (the NDP won the 1996 election even though the Liberals had more votes).

The third-place Green Party is seeking to add to its lone member in the legislature – Leader Andrew Weaver – and could serve as a potential spoiler for the NDP. The party's support has sat just over eight per cent in the past two elections, though it has been falling slightly rather than growing. The Greens have bolstered their campaign machinery this year, staging a traditional bus tour for the first time – using a biodiesel vehicle, of course – and are also running internal polling to identify key ridings.

The BC Conservatives were seen as a threat to the Liberals in 2013, when poll numbers suggested a possible breakthrough, but the party earned less than five per cent of the vote. It enters this year's campaign without a leader, shut out of the television debate, and with just eight candidates in place.

Housing

Skyrocketing housing costs have sent the Vancouver region's housing market into crisis, with sale prices increasing by more 40 per cent in a single year and detached houses now out of reach for a wide section of the population. For those who can't buy, rental rates have also climbed significantly in a region where vacancy rates sit at less than one per cent.

The government has spent the past year introducing a series of policies designed to calm the housing market, including a tax on foreign buyers in the Vancouver region; legislation to allow cities to tax vacant homes, which the City of Vancouver has done; and a loan program for first-time buyers. Critics have said the measures are too late, and have blamed the Liberals for watching idly as housing prices spiralled out of control.

The New Democrats have yet to release their full platform, but have called for a tax that focuses on speculation, rather than citizenship, and have promised to build more rental housing.

Economy

Expect the Liberals to point to economic statistics that show the province leading the country in employment and economic growth. For example, March employment figures show B.C. had employment growth of 3.8 per cent compared with a year earlier – the highest among the provinces. The Liberals will also warn that an NDP government would put that at risk and revive claims that the province's economy performed poorly under the New Democrats in the 1990s.

That economic growth, however, has not been evenly distributed. The unemployment rate was as high as 9.7 per cent in northern areas of the province last year, and most regions outside Vancouver and Vancouver Island lost jobs last year compared with 2015.

For the NDP, one of the big economic questions will be how the party plans to pay for expensive promises that include $10 per day daycare, along with eliminating tolls on two Vancouver-area bridges and freezing electricity rates. The party has suggested it will increase taxes on the richest British Columbians.

Education and child care

The province's education system is about to undergo a massive overhaul due to a Supreme Court of Canada decision last year over bargaining that will force whoever wins the election to hire thousands of teachers and support staff.

The NDP have long criticized the Liberal government for short-changing students and starving the school system of resources. The Liberals will also have to fend off attacks from the B.C. Teachers' Federation, which put out an ad in March urging voters to elect a government "we can trust with our kids' education."

One of the NDP's central promises will be $10-per-day daycare, similar to the system already in place in Quebec. There is currently no timeline for when it would be up and running, and many of the specifics have yet to be announced. The Liberals are also promising to create thousands of new child-care spaces, but argue the NDP plan would be unaffordable.

Campaign finance

British Columbia has earned a reputation as the "wild west" of campaign finance – a place that imposes almost no limits on the influence of money in politics. The province has no caps on donations, nor does the law place any restrictions on whether corporations, unions, or foreign donors can give. The BC Liberals have been criticized for holding private cash-for-access events in which donors pay thousands of dollars to dine with the premier or other cabinet ministers.

As well, a recent Globe and Mail investigation found lobbyists made donations in their own names using money from the companies they represent. Such indirect donations are prohibited under the law, and the RCMP is now investigating the fundraising practices of the province's political parties.

The New Democrats have pledged to ban corporate and union donations while condemning the Liberals as "bought and paid for." Still, the NDP has actively solicited such donations and held its own fundraising events featuring its leader.

Ms. Clark recently promised to appoint a panel to review campaign finance laws. While she opened the door to the possibility of donation limits, she did not say what sort of reforms, if any, she would prefer. She did, however, say that any new system must not rely on public subsidies.

Pipelines

The federal government approved the Trans Mountain pipeline project, which would expand Kinder Morgan's existing line between Alberta's oil sands and the Vancouver region, last year and the B.C. government gave its own approval in January.

Ms. Clark will argue that her government successfully fought for better oil spill protection and economic benefits for the province, while the New Democrats, who have pledged to kill the project, say the risks are too great.

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