Saturday’s Senate by-election in Western Australia is certainly good news for the environmental party. The Greens polled nearly 16% of the primary vote, a result that saw Scott Ludlam handily re-elected with quota to spare. The result represented a swing to the Greens of more than 6%.

Ludlam’s result is a personal triumph for the soft-spoken Western Australian. After narrowly losing his seat in the contested result of 2013, Ludlam has roared back into the Senate for another six years on the back of a highly effective Greens campaign.

Beginning with the unexpected social media success of his “Welcome to Western Australia, Tony” speech, Ludlam honed a re-election campaign that was well targeted and technologically savvy. He leveraged his excellent online profile and policy expertise on issues like the NBN and surveillance to attract a wider following of voters under 40. In just a month, Ludlam has tweeted and DJ’d his way from likely has-been to future leader.

While Saturday’s result may not herald a new age of verdant ascendancy, it does have some important implications for those keen to write off the Greens as a political force in Australia. Their demise is regularly forecast by major party figures and journalists, many of whom appear to believe that the environmental party will one day share the fate of the Australian Democrats.

Recent events appeared to add weight to the theory. In recent years, the Greens vote has been going backwards from its historic high at the 2010 federal election. A disappointing result in 2013 was followed by a poor outcome this year in the minor party’s heartland of Tasmania, where voters punished it for four years of unpopular coalition government with Labor’s Lara Giddings. The negative momentum fuelled plenty of anti-Greens schadenfreude from the party’s enemies in Labor and the right, and stoked rumours of a leadership move against Christine Milne.

Media commentators joined in the fun, penning anti-Milne pieces like this recent one from Fairfax’s Mark Kenny, in which he makes the claim that there is a “vibe of genuine concern, bordering on insurrection running through the Greens right now.”

Ludlam’s victory puts paid to the theory that the Greens are inevitably on the way out. If anything, it shows that the party retains its electoral base to the left of Labor, and has further potential to eat into Labor’s vote should the ALP continue to under-perform. Ludlam appears to have picked up most of his swing from disaffected ALP voters, who deserted Labor in the wake of a disastrous final week. The ALP polled only 22%.

The contrast between Ludlam’s slick embrace of social media and Labor’s disastrous campaign could not have been starker. Labor is still struggling with the internal reform it clearly requires, if only to present electable candidates to the voting public: factional machinations resulted in the pre-selection of a candidate, Joe Bullock, who appears to loathe his own supporters. Out of office in state politics since 2008 and holding only three of 15 house of representatives seats, Labor is in a parlous state in the west.

A Senate by-election in Western Australia is by definition an unusual event, and we should be wary about drawing sweeping conclusions. But Saturday’s result does seem to underline a growing trend away from the major parties, and towards minor parties of both the right and left. This gels with plenty of evidence from the social sciences, which has been warning of a growing dissatisfaction with politics as usual for decades now.

Between 1949 and 1996, the total Senate vote for the major parties never fell below 80%, even accounting for the DLP. In 2013, it was 68%. On Saturday in WA, even throwing in the Nationals, it was 59%. Voters are less loyal to the old Liberal-Labor dichotomy than ever. Tony Abbott and Bill Shorten would be unwise to ignore the warning signs.