Jokes aside, it is the people with millions of dollars in campaign budgets, and who are extremely well-compensated, who are responsible, along with others with genuinely large platforms. I don't think this humble blog has zero influence on the world - and I do take that tiny responsibility seriously - but it is much much less than that of the CNN green room residents, your NYT "liberal" columnists, and the CEO of the Center for American Progress.
If things go well in the midterms, all of those people will take credit. If they don't, they will be desperate to blame people with much less power than they have.
And if those people can't pull it off when Republicans are this unpopular...