In Dallas this week, Donald Trump offered every American adult a $5,000 promise — contingent on Republican victory in November's midterms — a pledge as large and unanchored as the empty seats that quietly contradicted his claims of a packed arena. The moment captured something enduring about this political era: the gap between the spectacle of power and its actual hold on the public. History has long punished the party in the White House during midterms, and Republicans are wagering that one man's gravitational pull can bend that pattern — a bet whose odds are written, in part, in the silence