Next May Britain is all but certain to hold a referendum on the alternative vote. It was striking, at all three party conferences, how little excitement there was about this. Liberal Democrats, who arguably have the most to gain from a yes vote, launched a half-hearted campaign to secure it but Nick Clegg's mention of the referendum in his conference speech produced only modest applause. Most Lib Dems see AV as a poor substitute for proper proportional representation. They would prefer a yes to a no, but their hearts are not in it.

Meanwhile Labour, which committed itself to an AV referendum in its last general election manifesto, came across as distinctly hostile to it at its conference. Ed Miliband promised to vote yes in his speech, but he did not say he would campaign hard for a positive outcome. Many Labour supporters have come to fear AV as a government plot, intended to keep the opposition out of power. The irony is that when Gordon Brown backed AV before the election, many Tories suspected exactly the same thing.

The Conservative party, whose MPs are being whipped in order to get legislation allowing a referendum through parliament, was overwhelmingly hostile. The small band of Conservatives who support electoral reform – some of them from Wales and Scotland, where the party has benefited from it – are critical of AV. A fringe meeting intended to drum up Tory support for a yes vote instead saw every speaker explain why full proportional representation would be better. The no to AV campaign has been licensed by the party leadership as a safe outlet for Tory discontent with the consequences of coalition.

So the mood among the political classes is underwhelming. AV is loved by no one, and distrusted by many. Most commentators have discounted the chances of a yes vote next May. But they are being too hasty. It is true that a negative outcome is more likely than a positive one, but defeat is neither inevitable nor something to wish for. Few voters can have thought hard about the issue. The campaign could make a big difference either way. But for now public opinion is split rather than opposed. In August a Guardian/ICM poll found 45% would vote yes and 45% no. If politicians seem hostile to AV, voters may even begin to warm to it.

There are weaknesses in the system, but the question people should ask is whether AV is an improvement on first-past-the-post. The answer is yes. It allows choice. It requires every MP to get the support of at least half their constituents. It stops votes being wasted. It is appropriate for a democracy no longer dominated by two big parties. Reformers in all parties must shed their reticence and campaign for a yes.