A concrete agenda and landslide victory might not even guarantee a president his mandate in a capital as polarized as Washington.
Barack Obama won a second term but no mandate. Thanks in part to his own small-bore and brutish campaign, victory guarantees the president nothing more than the headache of building consensus in a gridlocked capital on behalf of a polarized public.
If history is a guide, a victory for Obama means he faces the prospect of a second term dogged by scandal or inertia.
Andrew Jackson was the first president to claim that the desires of the public overrode Congress's constitutional prerogatives. Virtually every president since Jackson has claimed the mantle, even while lacking two ingredients of an electoral mandate: a landslide victory and a specific agenda.