To Whom It May Concern,
Please allow me to offer my congratulations on your election to office. Depending on the exact circumstances, this is a testament either to your general excellence, or to the deep incompetence of your opponents (or possibly to a combination of the two).
I would like to offer – if I may – a single piece of advice: do not, under any circumstances, publicly complain about the inadequacies of your predecessors or the mess they have left. You will sound like a petulantly whining child. Rather, explain plainly the state of things as they are, and your bold plan to bring us to a better future. Many of us are not idiots, and will respect (and even vote for) competent adults, assuming we are able to find any.
All the best for the next few years.