The past three times British Columbians went to the polls to choose their provincial government, the outcome was almost identical.

Over that period, political leaders have changed, the economy shrank and grew, demographics shifted and third parties on the left and right have gathered and lost steam.

And yet, in each outing, the BC Liberals won a solid majority with about 45 per cent of the popular vote, and the New Democrats remained in opposition, falling short of victory by just a few percentage points.

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As the parties head into the four-week campaign that begins on Tuesday, the NDP has a steep hill to climb if it is to break through and form government: It must hold its current seats, including some won by razor-thin margins. It must keep the BC Greens from taking a growing share of centre-left voters. And it needs to capture not just weak Liberal ridings, but seats where Liberal candidates won with a relatively comfortable surplus of votes.

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The Liberals have their own set of challenges. Gone is the urgency that rallied supporters in 2013 when the party was supposedly 20 percentage points behind the NDP in the polls. Scandals and dubious achievements – cash-for-access fundraisers and a 10-year freeze on welfare rates to name a couple – are now firmly attached to Premier Christy Clark's leadership.

Mike McDonald served as director of the BC Liberals' successful election campaign in 2013. He spent that past campaign insisting the party could beat the odds and win. This time, he is warning that the party's hold on government is in peril. When he spoke at a recent meeting of the party's governing council, the theme of his address was the "reasons we could lose."

In that speech, Mr. McDonald sought to jolt Liberals out of a state of complacency. With the exception of their rout of the New Democrats in 2001, the number of votes that separate victory and loss are uncomfortably small. The New Democrats have captured at least 39 per cent of the vote in 10 of the past 11 elections, and can count on a formidable team of allies from labour and other third parties to shore up their volunteer forces.

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There is uncertainty, he also warned, about the role the BC Green Party will play in this campaign. The Greens have enjoyed significant public exposure through their lone MLA, Andrew Weaver, in the legislature for the past four years. Not only could the Greens gain seats when the votes are tallied on May 9, but they could upset the two-party system that has worked in the Liberals's favour, generating three-way contests where the outcome is anything but predictable.

British Columbia Green Party Leader Andrew Weaver, front left, walks to a news conference after unveiling his new election campaign bus in Vancouver on April 6, 2017. DARRYL DYCK/THE CANADIAN PRESS

Incumbency is an advantage – until it isn't. The Liberals are seeking a fifth consecutive term at a time when voters – in the federal election, in the United States and next door in Alberta – have favoured change. The Liberals may be at that point, after 16 years of governance, where the baggage gets too heavy.

Mr. McDonald pointed out that the New Democrats will not constrain themselves to a strictly positive campaign as they did in the past election, and will highlight Liberal negatives at every turn.

Current legislature makeup Party Seats Liberal 47 NDP 35 Green 1 Independent 2

However, the Liberals have had the luxury of a well-stocked war chest to improve the odds. The party posted a surplus of $7.6-million last year, and has reaped millions more in the first three months of 2017. They also benefit from having a well-rehearsed campaign team, bringing back most of the same key players who delivered their 2013 victory – Mr. McDonald and strategist Don Guy are senior advisers, while Liberal pollster Dimitri Pantazopoulos is back running the numbers and focus groups to test out campaign messages. Brad Bennett, of the Social Credit dynasty, will again join the Premier on the bus as her confidant and sounding board.

And, not insignificantly, the Liberals have the good fortune to be able to point to a top-performing economy and job-creation record among the provinces. (It's an uneven performance and not all British Columbians have benefited, but the top-line numbers serve the Premier's jobs-first mantra well.)

Training camp

The millions amassed through political contributions have helped fund, among other things, the Liberal's most elaborate training camps for its candidates and campaign managers to date. In 2013, with a leaner budget, the party relied on Internet-based seminars for training. For the past 15 months, the party has been running a campaign management "college" that includes weekend-long, in-person training sessions.

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The New Democrats have a fresh face on the side of their campaign bus: John Horgan replaced Adrian Dix after the party's unexpected defeat in 2013. Not surprisingly, the NDP did not bring back the previous campaign team. Bob Dewar, recruited from the Manitoba Government and General Employees' Union, is campaign director. Raj Sihota is the party's provincial director and Glen Sanford, as deputy director, heads up media relations.

The party raised half as much money in donations as the Liberals last year and it has not yet paid off its debts from the 2013 campaign, so spending has to be more strategic.

British Columbia NDP Leader John Horgan addresses supporters after unveiling his election campaign bus in Burnaby, B.C., on April 4, 2017. DARRYL DYCK/THE CANADIAN PRESS

The New Democrats have conducted extensive training for volunteers, as well, although most of the work has been carried on over online conferencing. Over the past two years, the party has trained more than 2,100 campaigners – an extensive effort compared with past campaigns.

What does training look like? The NDP's "Forward" curriculum includes communications and fundraising training, and lessons on "Demystifying Data-Driven Campaigns." It coaches recruits on how to maximize conversations with voters and on digital organizing.

Facts on the ground

While the parties face different challenges, some factors are universal: This campaign will be much more of a ground war.

Voters can expect more in-person appeals on the doorstep than supper-hour telephone interruptions this time around. That is because, as more people abandon traditional home phones in favour of cellphones, campaign phone banks are becoming ineffective. The average match between the provincial voters list and the public phone book (old-time campaigners would recognize them as "the white pages") now is just 55 per cent, and cellphone lists are not for sale.

It means connecting with undecided voters will require more intensive door knocking than cheap-and-fast phone banks.

British Columbia Premier Christy Clark arrives for a news conference after addressing the Council of Forest Industries convention in Vancouver on April 7, 2017. DARRYL DYCK/THE CANADIAN PRESS

This weekend, the New Democrats say they'll mobilize 1,000 volunteers to canvass; the Liberals will also be out in force for a "super Saturday" campaign blitz.

Both main parties will spend significant portions of their campaign budget (each is capped at $4.7-million during the four-week campaign) on advertising. Newspaper, television and radio ads will continue but digital supplements will grow. The online ads are not just cheaper, but many people are consuming their news on tablets and smartphones, so both the NDP and Liberals have boosted the share of resources for digital campaign teams.

Picking their fights

One of the main tactical decisions of any campaign is to choose which ridings to focus resources on – a calculation that evolves as Election Day nears.

Last week, while Ms. Clark maintained a low profile, the NDP got an early start on the campaign. Mr. Horgan unveiled the campaign bus and brought reporters to the Premier's Westside-Kelowna riding in a bid to frame the election around her negatives.

Despite his foray into strong Liberal territory, the focus will be on key swing ridings. "There are some places we have to be realistic," said a chief New Democrat strategist. This time around, the NDP doesn't intend to spend energy and resources trying to win solid Liberal seats.

Kamloops and Prince George have traditionally been viewed as bellwethers, where voters have an uncanny knack for picking winners. But the key battlegrounds will be about 20 seats where the votes were close in 2013.

The electoral boundaries have been redrawn for 2017, making two more ridings for a total of 87 seats. The parties know at the start of the campaign which ridings they have to defend, and where their opponents are weakest. But as the campaign evolves, they will depend on more detailed polling and feedback from canvassers to pinpoint where the fight will be.

Using the 2013 data and applying it to the new boundaries, here are a few examples of ridings that are expected to be closely contested:

Surrey Fleetwood: Under the new riding boundaries, high-profile cabinet minister Peter Fassbender would have lost this seat.

Burnaby-Lougheed: It's at the epicentre of the Kinder Morgan oil pipeline debate; the NDP won it by about 700 votes, but incumbent Jane Shin is not running again, while the Liberals have nominated a high-profile media personality, Steve Darling. The Greens, with punk rocker Joe Keithley as their candidate, could siphon off anti-pipeline voters who would otherwise support the NDP.

Saanich North and the Islands: Traditionally a Liberal riding, the NDP won this seat by just 163 votes in 2013, in a close three-way race with the Greens.

All eyes on the leaders

Those ground-war tactics are mostly carried on out of the public spotlight. It is the leaders who are in the spotlight each day, responsible for delivering the high-level campaign messages.

Ms. Clark is going to stick to what worked so well for the Liberals in 2013, when she was seen every day talking about jobs and the economy. She'll look for every opportunity to be appear with workers – ideally, wearing her signature hard hat. She will once again cast the Liberals as the party of Yes on economic growth and resource development – and attack the NDP as the party of No.

Mr. Horgan, who is a more gregarious and scrappy leader than Mr. Dix, is aiming to hold the Liberals to account for their 16-year record. Although his party will run negative ads this time, his strategists say there will be a careful balance with solid commitments for change. The party will focus on promises to make life more affordable for British Columbians, to "build an economy that works" and to ensure that public services are there for those who need them.

After months of intense fundraising and training and strategizing by the parties, the campaign formally launches on Tuesday. And all these plans can be tossed aside in a heartbeat. Because if there is one lesson learned in 2013, it is that campaigns matter, and no-one can say for sure what voters will do when they drop their ballot in the box on May 9.

B.C.'s battlegrounds

Results from the 2013 election based on new riding boundaries in place for the coming vote

Coquitlam–Maillardville Lower Mainland – Greater Vancouver Votes Percentage NDP 9,305 45.7% 0.3 Liberal 9,234 45.4% Green 1,782 8.8% Other 11 0.1% Saanich North and the Islands Vancouver Island and the Sunshine Coast Votes Percentage NDP 10,510 33.3% 0.5 Liberal 10,346 32.7% Green 10,140 32.1% Other 600 1.9% Delta North Lower Mainland – Greater Vancouver Votes Percentage Liberal 9,611 44.5% 0.9 NDP 9,410 43.6% Green 1,316 6.1% Conservative 976 4.5% Other 287 1.3% Surrey–Guildford Lower Mainland – Greater Vancouver Votes Percentage Liberal 7,116 44.5% 1.7 NDP 6,847 42.8% Conservative 1,779 11.1% Other 268 1.7% Port Moody–Coquitlam Lower Mainland – Greater Vancouver Votes Percentage Liberal 10,322 46.4% 2.1 NDP 9,855 44.3% Green 1,815 8.2% Other 229 1.0% Vancouver–Fraserview Lower Mainland – Greater Vancouver Votes Percentage Liberal 10,119 46.7% 2.2 NDP 9,647 44.6% Green 1,232 5.7% Conservative 649 3.0% Maple Ridge–Pitt Meadows Lower Mainland – Fraser Valley Votes Percentage Liberal 10,820 45.5% 2.6 NDP 10,205 42.9% Green 2,175 9.1% Other 589 2.5% Burnaby North Lower Mainland – Greater Vancouver Votes Percentage Liberal 9,926 46.8% 2.9 NDP 9,315 43.9% Green 1,488 7.0% Other 480 2.3% Burnaby–Lougheed Lower Mainland – Greater Vancouver Votes Percentage NDP 9,512 44.2% 3.2 Liberal 8,817 41.0% Green 1,754 8.1% Other 1,433 6.7% Fraser–Nicola Cariboo – Thompson Region Votes Percentage Liberal 6,304 43.6% 3.2 NDP 5,840 40.4% Green 1,121 7.8% Conservative 1,028 7.1% Other 170 1.2% Surrey–Fleetwood Lower Mainland – Greater Vancouver Votes Percentage NDP 8,528 46.9% 3.4 Liberal 7,901 43.4% Green 946 5.2% Conservative 724 4.1% Other 62 0.3% Skeena North Votes Percentage NDP 5,605 47.7% 4.4 Liberal 5,084 43.3% Conservative 792 6.7% Other 276 2.3% Vancouver–Point Grey Lower Mainland – Greater Vancouver Votes Percentage NDP 11,495 47.6% 4.4 Liberal 10,439 43.2% Green 1,634 6.8% Conservative 382 1.6% Other 192 0.8% North Vancouver–Lonsdale Lower Mainland – Greater Vancouver Votes Percentage Liberal 10,524 45.3% 4.6 NDP 9,464 40.7% Green 2,172 9.3% Conservative 796 3.4% Other 301 1.3% Note: Percentages rounded to nearest decimal place

Source: Elections BC

Graphic by Danielle Webb

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