AHC: Make every election from 1968 close

What the hell, I'll give it a go:

1972: Have Nixon's first term go worse than it did (but not enough to cost him re election) and have Musike emerge as the Democratic nominee. Muskie picks a southern running, runs a good campaign, and keeps the entire party behind him while Nixon runs a slightly worse campaign than OTL. It could still be a decisive win for Nixon in the EC, but the popular vote would be close.

1976: no challenge there, as it was close.

1980: Keep Kennedy from primary challenging Carter, have Reagan run a worse campaign, and have Anderson run a better one, getting support close to Perot's in 92 or 96. Also, have carter participate in the first debate with Anderson

1984: Give Gary Hart the Democratic nomination and have him pick a better running mate than Mondale did. Reagan's age shows on the campaign trail and in both debates. Hart, like Muskie, still loses, but the election is closer than OTL.

1988: Simple. Dukakis responds to the attacks thrown at him and hammers Bush on Iran Contra and his ties to Noriega. Keep Reagan off of the campaign trail and you have a close election that could honestly go either way.

1992: Perot doesn't drop out and re enter or talk about Republicans sabotaging his daughter's wedding. Bush runs a stronger campaign than OTL OR have Perot stay out in general. Clinton still wins but the election is closer in either case.

1996: The GOP doesn't overplay its hand after 1994, so there's no Government shutdown, making it harder for Clinton to recover from the blunders of his first two years, thus making him more vulnerable going into the election. Dole as a result gets a better funded and run campaign. Also, have Perot run a stronger campaign and somehow allow him into the debates.

2000: Need I explain

2004: No need to go into this one either.

2008: An earlier surge and a better response to Katrina make Bush a little less unpopular at the end of his term. Give McCain's campaign a better vetting process for VP, avoiding the Palin debacle. McCain also can't make an ass of himself when responding to the financial crisis either ("the fundamentals of our economy are sound," suspending his campaign to go back to Washington, etc...). Do all this, Obama's win is much narrower.

2012: No 47% remark, make Romney less gaffe prone overall, and have him perform better in the second and third debates. Having the Bin Laden raid fail and/or having the Eurozone crisis trigger a recession in late 2011 or early 2012 would make Obama more vulnerable and possibly give Romney a close win.

I don't know how plausible these are, but this is the best I can think of.
 
Humphrey win 1968.

Republican run a far right candidate against Humphrey 72, who loses narrowly

Muskie narrowly loses in 1976, perhaps to a moderate. Dems run McGovern who is seen as too extreme so that moderate Republican holds on narrowly in 1980 despite economic problems.
 
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