In theory, a uniform 4% swing (or 8% depending on how you define swing) would have given Carter an EV victory and a PV loss in 1980. (Illinois was the tipping State, so with a uniform swing Carter needs to win Illinois and all closer States.) Unlikely, and it certainly would require a counterfactual such as Operation Eagle Claw being a success to have happened.
Reagan himself would probably be gracious, but Republicans would likely blame Anderson, with some degree of truth as much of Anderson's strength came from liberal Republicans unwilling to vote for either Carter or Reagan. In the actual 1980 election, even if every Anderson vote had implausibly gone for Carter, Reagan still wins easily, just with less of a landslide.
282 or 283 EV for Carter depending on whether he wins both of Maine's districts.
People would be talking about East-West tensions and not referring to the Soviets.
