That's not what populism is. Populism is when an elite claims to speak and act on behalf of the people without real input from them.
If you have a free and fair ballot, whether they get a majority, a plurality, or just a not-first-place minority of the ballots cast does tell something about the degree of popular support, by definition.
Not all balloting is free and fair, and not all electoral systems choose a winner the candidate with the most support as measured at the polls, such as systems that incorporate anti-democratic features designed to give certain voters more power per voter than others, like the US electoral college.
I disagree.
With electoral systems in which a candidate can win with ten percent of the vote (because nobody else scored more than ten percent), or where a party can win 12% of the vote and end up with 0.15% of the seats (as a specific example from recent western history), a politician being elected is simply not a measure of speaking for the people.
There’s more to it than that. For example someone could be elected though not desired by the majority (as has happened in US presidential elections a few times, and also happens in various places where more than two candidates vie for a seat).
Also there Re situations where the majority will egregiously violates the rights of minorities.
Or when there is a muddy signal, where Brexit is a good example: some people wanted any possible Brexit, others wanted it assuming certain conditions that are now clearly not going to happen; what is the popular will in this case?
I’m not saying that being elected isn’t the most important element, but it’s not only not sufficient, but it can actually be wrong.
The person that responded to you employed a classic "anti-rightward" trope equating populism to vicarious elite control. I fail to see the difference between Populism and Democracy on the "people" side of the equation, rather the difference is in which elites are pulling the strings.
„Populism is a range of political approaches that deliberately appeal to 'the people', often juxtaposing this group against the "elite".“
There is plenty of left-wing populism, by the way. Jeremy Corbyn, Chavez/Maduro, Yannis Varoufakis, etc.
And no doubt it applies to leftists, absolutely. That's the basis of a lot of right wing views: that the left is simply being populist and doesn't give a shit about actually improving life, but instead staying in power.
Of course, that's about the left's view of the right as well. Hmmmm.
If one had to align them left to right, they would look like:
Sanders -> Clinton -> Bush -> Trump .
> I fail to see the difference between Populism and Democracy on the "people" side of the equation
Democracy is a system of government, Populism is a manner in which a hopeful leader (often a candidate for leadership position in a democracy) attempts to appeal to the public. They aren't even in the same domain.