NIGEL Farage is sadly not a mirage. Instead he is canny operator who rides every wave he mounts. Unlike Ed Miliband, who wobbles off every passing wave.

So while Farage bestrode the giddying surf after Ukip’s second by-election victory last week, Miliband took a tumble thanks to a tweet. Now I’d like to have a lot of time for Mr Miliband. He seems impassioned and far-sighted in many ways. Trouble is, he has such a clumsy touch.

The Ukip victory in the Rochester and Strood by-election, following an early success at Clacton, should have been a moment for double Tory humiliation. Instead of which, Miliband flew into a fury after the shadow attorney general Emily Thornberry tweeted a picture of a house in Rochester decked out in St George’s flags, with a white van parked in the drive.

This seems like the silliest thing to have caused such a storm, but that’s modern politics for you, a 24-hour-news scrap-fest with the “scandals” falling faster than rain. Ed duly tied himself in knots as he spoke about his reasons for sacking Thornberry, and his earnest answers to questions about what he felt on seeing St George’s flags were truly excruciating. He should have found a smarter response than despatching someone for a mildly ill-advised bit of Twitter nonsense.

Instead, he grabbed the spotlight before it could illuminate the humiliated Tories and pointed it at himself instead.

Here’s a question though and one I’ve not heard asked anywhere yet: why were these by-elections held at all? Farage was cleverly playing the system, as he does, by having two defecting Tory MPs stand again for Ukip in their old seats. But these were what you might characterise as vanity by-elections, pointless polls held so close to a general election, and serving no purpose other than to draw attention to Ukip.

Surely if someone jumps ship from one party to another in the shadow of a general election, the vote should be held until polling day. All that money, effort and accompanying media steam could have been saved, and fewer pictures of a grinning Mr Farage would have been inflicted on the unsuspecting public (sincere apologies for the one here).

Ukip is certainly spreading its appeal, but only by offering an uneasy, ever-changing array of policies picked from right (quitting Europe, immigration) and left (blaming big business, speaking up for the NHS).

Yet how can such disparate views settle in one party? Policies plucked so opportunistically will eventually lead to massive contradictions, won’t they?

Also, it’s a funny sort of “people’s party” that’s led by a privately educated ex-City broker. Having an easy way with a populist quote and a pint have taken Farage far.

The effect Ukip will have in the general election is difficult to guess. Next year’s head-banging contest is the hardest to read in ages. Perhaps one way to look at Ukip is to recall the SDP, another small party that grew temporarily big, then disappeared, although not without helping to shape what followed, including the emergence of New Labour (remember them?).

One challenge facing populist new parties lies in the diminishing returns of novelty: the longer they are around, the more they become like other parties.

Ukip is still at the new boy stage, puffed up with the excitement of it all, but this won’t last. The more power they have, the more chance people will have to examine what they are like in action.

For now, the other parties need to expose Ukip to proper scrutiny. And they need to stop playing Mr Farage’s games by letting his small party set every other agenda, then stepping back to watch the scrap. Imitating Ukip is a pointless game that leaves the other parties looking foolish, especially Labour.

As for David Cameron, he promised to “throw the kitchen sink” at the most recent electoral contest. He lived up to his word and Rochester and Strood was littered with bits of broken sink, not that his efforts had much effect.

Finally, I do like the way that almost every Ukip spokesman utters the same mantra – “Vote Ukip and get Ukip.”

Well, yes, and that’s surely the problem.