Tipping Points

Nate Silver's old definition of the "Tipping Point" state would be: "the state that, when states are ranked by margin of victory, officially tipped the election to the victorious candidate."

Here's the margin of victory ranked list, along with the available electoral votes and the running total...

State	McCain Margin	Electoral Votes	Running Total
DC	-86	3	3
Hawaii	-45	4	7
Vermont	-35	3	10
Rhode Island	-29	4	14
Massachusetts	-26	12	26
Illinois	-25	21	47
New York	-25	31	78
California	-24	55	133
Delaware	-23	3	136
Maryland	-23	10	146
Connecticut	-21	7	153
Maine	-18	4	157
Washington	-17	11	168
Michigan	-16	17	185
New Jersey	-15	15	200
New Mexico	-15	5	205
Wisconsin	-13	10	215
Nevada	-12	5	220
Oregon	-12	7	227
New Hampshire	-11	4	231
Pennsylvania	-11	21	252
Minnesota	-10	10	262
Iowa	-9	7	269
Colorado	-7	9	278
Ohio	-5	20	298
Virginia	-5	13	311
Florida	-2	27	338
Indiana	-1	11	349
North Carolina	-1	15	364
Missouri	1	11	375
Montana	3	3	378
Georgia	5	15	393
North Dakota	8	3	396
Arizona	9	10	406
South Carolina	9	8	414
Texas	11	34	448
South Dakota	12	3	451
West Virginia	13	5	456
Mississippi	14	6	462
Tennessee	15	11	473
Kansas	16	6	479
Nebraska	16	5	484
Kentucky	17	8	492
Louisiana	19	9	501
Arkansas	20	6	507
Alabama	22	9	516
Alaska	26	3	519
Idaho	26	4	523
Utah	29	5	528
Oklahoma	32	7	535
Wyoming	32	3	538

And the winner is... Colorado! McCain could have won all of Ohio, Virginia, Florida, Indiana, and North Carolina, and Obama still would have won the election. Obama had a comfortable margin of victory, indeed. He won Colorado by 7 points, and he won the general by 6.5 points.

On Edit: Nate Silver just ran this same post with more updated numbers. He technically beat me to the punch.