It may seem odd to find an answer to this question in a book published in 1889, but if one can ignore merely local labels of party, Trevelyan expressed well the way in which consensus can be overturned by the cumulative effect of many small efforts at persuasion.
“But the outward aspect of the situation was very far from answering to the reality. While the leaders of the popular party had been spending themselves in efforts that seemed each more abortive than the last, –dividing only to be enormously outvoted, and vindicating with calmness and moderation the first principles of constitutional government only to be stigmatised as the apostles of anarchy, [Here my analogy temporarily loses it as some of our more enthusiastic brothers leap to their feet and cry, “Way to go, baby! Down with government! Anarchy forever!”]–a mighty change was surely but impeceptibly effecting itself in the collective mind of their fellow countrymen.
“For while the tired waves, vainly breaking,
Seem here no painful inch to gain,
Far back, through creeks and inlets making,
Comes silent, flooding in the main.”
– Sir George Otto Trevelyan, Bart, The Life and Letters of Lord Macaulay.
