Of course, it is easy enough to get elected to be leader of the opposition; as leader of the Opposition, Corbyn's mandate is to lead the party into the next election, and into government; whether that is possible is an open question. One common narrative says that Corbynmania is a purely emotive movement, grasping for the comfort of a fantasy, or the righteousness of the lost cause, much in the way that the hopeless embrace apocalyptic religion or conspiracy theories, and that, in the dozens of Tory marginal seats Labour will have to win back, it's unlikely to find traction. The implication of this narrative is that the opposite, a skilful rightward-triangulating neo-Blairism, cheekily ambushing the Tories on their own ideological turf, whilst offering the slightest essence of a brighter alternative—socialism diluted to homeopathic proportions, so not one particle remains—to somehow push the feeling that a Labour government implementing neoliberal privatisation/austerity policies will be ineffably better. This neo-Blairite model would place the running of the country in the hands of technocratic management, operating under a neoliberal free-market framework (as There Is, after all, No Alternative), communications with the fickle masses in the hands of spin doctors and, essentially, disinformation specialists, and whatever policy is not dictated by the markets and the needs of corporate stakeholders would be subject to focus groups and opinion polls. Standing for something is for losers, after all.
There are several problems with this argument; not least of them the fact that the Labour Party fielded three candidates who were driven by such calculation, who did dismally. Indeed, the one who did the worst was the one who most honestly articulated a Blairite centre-right position of the sort that, we are told, is catnip to the ordinary voter (the ordinary voter; that sharp-elbowed aspirational creature that reads the Evening Standard and is concerned primarily about their property values). The other two kept it artfully vague, avoiding committing to anything that might be held against them, hitting the talking points like pros, and even tacking to the left when it became evident that Corbyn had shifted the party's internal Overton window; it didn't do them much good. Had one of them won, it is hard to imagine their warmed-over, cobbled-together message stirring the electorate; especially whereas none of them had Blair's Mephistophelian charisma. (On the other hand, it can be argued that Tony Blair's uncanny election-winning power has been somewhat overstated; in 1997, the Conservative government was in such disarray, with a series of scandals and misfortunes topping a general sense of malaise and decay, that chances are anybody could have led Labour to victory.)
Anyway, it is now Corbyn's task (along with the newly elected deputy leader, Tom Watson, who's more of a pragmatist, whilst simultaneously passionate about issues of civil liberties) to lead the party into the next election and win. And one thing we can expect is that they will come under withering fire; from the Tories, the right-wing press, and even the more Blairite elements of their own party, should they sense the opportunity for a spill. From now on, the press will be full of hit pieces of varying degrees of hyperbole (look for mentions of “the Chavez of Canonbury”, for example). And perhaps the public will, after enough repetitions, start to believe them; polls will show Labour's support deteriorating; perhaps they will go into the next election and be thoroughly annihilated, swapping places with the Liberal Democrats; or not even get that far, as MPs, facing the loss of their seats, stage a spill and hurriedly put on their best Blairite act. But perhaps this time it won't work; if the Tories miscalculate, if too many of the public know people who have been thrown on the scrapheap by austerity, if the idea that those hit by welfare sanctions or the bedroom tax are the “unworthy poor” who have made their own misfortune through fecklessness suddenly loses its power, if millions of people realise that they're not temporarily embarrassed buy-to-let multi-millionaires but rather the deeply indebted precariat, and that the windfall they anticipate is not about to trickle down to them any time soon, the scare stories will be dismissed, and, being inured to them, the public will dismiss any concerns about Corbyn's views as similarly concocted.
Personally, I agree with some of Corbyn's views, but not all. He is my local MP, and I have, on occasion, written to him about various issues, and generally found my concerns well received. I'm not so keen on some of his other cited positions, such as, for example, withdrawing from NATO or the EU, or spending public health funds on ineffectual mystical quackery such as homeopathy. More significantly, Corbyn's idea of reopening coal mines seems backward in this day, when China and India are slashing their coal imports, coal-fired power plants are being deprecated and not replaced, and even coal-mad Coalition-ruled Australia is having a hard time funding its new coal mines. Corbyn's hope of reopening coal mines seems similarly ideological, only rather than impressing the bogan voters by punching the inner-city latte-sippers, it looks to be about avenging Arthur Scargill and the martyrs of Orgreave and sticking one up at Thatcher. Indeed, Corbyn doesn't seem to have said much about the environment or the threat of climate change, or the need to radically change our infrastructure to reduce its environmental impact.
However, Corbyn is not the autocratic leader of the Labour Party, and it seems that these positions are less likely to prevail than more popular ones (such as building massively more public housing, renationalising the railways, easing off on austerity and such).
In any case, we live in interesting times; as the last election (in which the SNP took almost a clean sweep of Scotland) showed, we can no longer rely on safe assumptions of how things will unfold.