The market has the perception that the powers that be will not allow the markets to falter ahead of the fall elections.
If that perception fails, look out below.
"Where such a shift in power is in favor of the governing elite, Power will achieve its murderous potential. It simply waits for an excuse, an event of some sort, an assassination, a massacre in a neighboring country, an attempted coup, a famine, or a natural disaster, to justify the beginning of murder en masse. Most state sponsored murder occurs under the cover of war, revolution, or guerrilla war, or in their aftermath."
R. J. Rummel