Best candidate losing party could nominate since 1948

[Kingpoleon]

1948: John Bricker: He's a charismatic Governor of Ohio who should have won and picked Warren or Dewey as his running-mate. Think Reagan thirty years early. Eisenhower wouldn't take the nomination.
1952: John Sparkman or Alben Barkley: They would have been far better at campaigning and running on continuing Truman's successes.
1956: Adlai Stevenson[1]
1960: Henry Cabot Lodge[2]
1964: George Romney[3]
1968: Eugene McCarthy[4]
1972: Henry Jackson[5]
1976: Ronald Reagan[6]
1980: Jerry Brown[7]
1984: Edmund Muskie[8]
1988: Paul Tsongas[9]
1992: Bob Dole[10]
1996: James Stockdsle/Jack Kemp[11]
2000: Joe Lieberman[12]
2004: Howard Dean[13]
2008: Rudy Guiliani[14]
2012: Jon Huntsman[15]

1: Stevenson was massively popular and rallied the base against EISENHOWER better than anyone could.
2: Lodge had much more foreign policy experience than Nixon and could downplay Kennedy's fear-mongering.
3: Romney was a moderate attractive to both sides.
4: McCarthy has the McCain maverick appeal to independents.
5: Jackson was charismatic and a great campaigner.
6: Reagan would have delivered a massively more popular campaign.
7: Brown also has maverick independent appeal.
8: Muskie can return to Nixon & Carter without being too close to Carter.
9: Tsongas ran a populistic campaign aimed for the general.
10: Dole had more independent support.
11: Perot and Stockdale already had great support from Independents and Democrats while Kemp was a very popular person.
12: Lieberman had huge neoconservative and independent support.
13: Dean rallied the base and independents.
14: Guiliani. How can you vote against someone named Rudy Guiliani?!?!?
15: Hunstman, for obvious reasons.

[Kingpoleon]

2008: Rudy Giuliani, his fiscally conservative, yet socially moderate views are in line with a majority of voters
2012: Rudy Giuliani, for the same reasons he was strong in 2008 but he'd have been aggressive in a general election

2008: Rudy Guiliani[14]

14: Guiliani. How can you vote against someone named Rudy Guiliani?!?!?

Mine was mostly satire, but he might have done a bit better than McCain.