Which Presidential Elections were probably "stolen"?

I.e. something nefarious happened either in the popular vote, the electoral vote, or even a House vote when the election was thrown into the house. A notorious example was 1876: Rutherford B Hayes vs Samuel Tilden.

1. 1876

The election was thrown into the House. Samuel Tilden won the popular vote and 184 electoral votes to Hayes's 165. But 20 electoral votes were disputed and went to Congress to decide. The Democrats controlled Congress so they decided that Hayes would win those 20 electoral votes, giving him the election.

2. 1960

I don't know what happened here but LBJ spent a lot of money in states he barely won (like Kentucky) and barely lost (like Texas).

3. 1964

LBJ vs Goldwater. LBJ spent a lot of money on TV ads in states like Pennsylvania, where he barely won, to make it look like he had a landslide victory over Goldwater.

4. 1968

Nixon vs Humphrey vs Wallace. Nixon narrowly beat Humphrey by about 500,000 votes (if I remember correctly). Wallace got 5 million votes but no electoral college votes because he didn't win any states. There are many theories that Nixon stole this one but I don't know for sure which are true and which aren't. - The Chicago Tribune printed an extra 1 million copies of its Sunday paper with "Nixon" on the front page instead of "Humphrey". This was widely believed to give Nixon momentum going into the next day's voting.- There were reports that Nixon operatives bought up all the phone books in some urban areas so people couldn't call each other and organize against him.- There were reports that Mafia hitmen were sent out to scare Wallace voters.- In Texas there were reports of dead people voting for Nixon.- In Illinois there were reports of stuffed ballot boxes, etc.

5. 1976-1988?

Jimmy Carter vs Ronald Reagan vs John Anderson (a third party candidate). Reagan got 43% of the vote and Carter got 38%. Anderson got 6%. But Reagan won easily with 50% of the electoral college vote. Why did this happen?- A few days before the election, polls showed a deadlock between Reagan and Carter but then suddenly Reagan started getting a huge surge in popularity.- Anderson didn't campaign at all in several key states where his support might have made a difference.- It was widely reported that pollsters changed their polling methods after seeing how off they were in 1972 when they predicted a landslide Nixon win instead of his razor thin loss.- It was also reported that both parties used computer modeling to determine who would be most likely to switch sides depending on how much money each side spent in certain districts or states.- It was also widely reported that Republican operatives infiltrated groups like ACORN and stole as much voter data as possible so they could find out who their potential voters would be (and then buy them off if needed).