For example the teapot dome scandal in the Harding administration. Harding was a republican who sold very valuable government owned oil fields to supporters for peanuts. His secretary of the Interior, Albert Fall took the blame and went to prison. The press referred to the secretary of the interior as Harding's Fall guy.
Did it hurt Reupbicans? Harding's Vice president was elected in 1924 with 70 percent of the vote. The republicans won huge majorities in the House and Senate. As far as election returns were conserned the Teapot Dome scandal was a tempest in a teapot.
Think that was a long time ago? Look how Iran Contra hurt Reagan and the Repubilcans? You say it didn't. I guess it hurt Republicans about as much as Whitewater and Monica hurt Clinton and the Democrats.
There is no historical president that election outcomes are determined by scandals. Yes Carter beat Ford after Watergate and Bush beat Gore after Monica. But the scandals were not the reason.
The odds of Democrats doing better in the house are quite slim. Democrats demanding that terrorists be free to talk to other terrorists embeded in the USA is the biggest loser I can imagine.
I guess 1990's Democrat Vice Presidents get a pass on that.
And during the Clinton years guess who got to take over the Elk Hills Reserve in California ?
Algore's family's patron, Occidental Petroleum.
Surprise !
Harding died before Teapot Dome erupted in full - if memory serves; he staffed his administration with cronies who took advantage of him, but I don't ever recall reading that he was thought to be involved in the graft.