3 -- a proportional or nearly-proportional split. The electoral college relates closely to having a federal system. Some states have low voter turnout and some have high voter turnout. Besides, I do not want any Presidential election ever decided by a low vote total that results from a natural disaster at the time of the election. That could have happened with Hurricane Sandy.
The Devil is in the details, so here is how one can do it. First, give two of the electoral votes of any state to the winner of the plurality. Then divide the rest by all performers in the Presidential election and preliminarily divide all electoral votes by the total vote. No fraction of an electoral vote will be offered. People who start fruitless write-in candidacies so that they can get recognition in Wikipedia for having won some tiny fraction of the electoral vote for winning four popular votes in California and none elsewhere would be ignored as now, and third Parties that get less than their share of one Electoral Vote would be ignored. Charles Manson could conceivably get a millionth of an electoral vote, and I doubt that we want to see that.
After that first round the remaining candidates would split the total votes allocated to them in proportion to the votes for that candidate, but only in whole numbers. Any remainder of the total of relevant votes (those allotted to those not ruled out for not getting enough votes to qualify in the first round) would go to the winner of the plurality.
Going with the states with the highest number of electoral votes first -- California:
Barack H. Obama Democratic 7,854,285 60.24% 55
Willard Mitt Romney Republican 4,839,958 37.12% 0
Gary Johnson Libertarian 143,221 1.10% 0
As you can see, Johnson (L) falls short of winning 1/53 (about 1.89%) of the total popular vote in California as do other third-party and independent nominees.
So after the first round Gary Johnson drops off because he does not win 1/53 of the total vote as do the other third-party nominees and we get
Barack H. Obama Democratic 7,854,285 60.24%
Willard Mitt Romney Republican 4,839,958 37.12%
Divide what remains relevant evenly into 53 electoral votes not allocated on a winner-take-all basis:
Barack H. Obama Democratic 7,854,285 61.87% 32.79
Willard Mitt Romney Republican 4,839,958 38.13% 20.21
Because there will be no fraction of an electoral vote, the winner gets his count adjusted upward, and we have -- after adding 2 to the winner of the plurality --
Barack H. Obama Democratic 7,854,285 61.87% 35
Willard Mitt Romney Republican 4,839,958 38.13% 20
California becomes a contestable state.
Now let's try Texas, with 38 electoral votes:
Willard Mitt Romney Republican 4,569,843 57.17%
Barack H. Obama Democratic 3,308,124 41.38%
Gary Johnson Libertarian 88,580 1.11%
Romney wins two electoral votes for winning the plurality in Texas. Divide the total vote by the vote for the different candidacies and one finds that Johnson falls far short of the 2.78% of the total vote necessary for winning an electoral vote in Texas. So what remains is
Willard Mitt Romney Republican 4,569,843 58.08%
Barack H. Obama Democratic 3,308,124 41.92%
Allocating 36 electoral votes one gets:
Willard Mitt Romney Republican 4,569,843 20.88
Barack H. Obama Democratic 3,308,124 15.12
Giving Romney the allotted two statewide electoral votes and the fractional vote one gets:
Willard Mitt Romney Republican 4,569,843 23
Barack H. Obama Democratic 3,308,124 15
So Texas becomes a relevant pace for campaigning. 'Swing votes' become relevant in such high-population areas as Orange County (California) and Dallas County (Texas). The count for the two biggest electoral prizes is
Obama 50 - Romney 43
on the assumption that the candidates do nothing different.
New York State and Florida both have 29 electoral votes:
New York (blowout)
Barack H. Obama Democratic 4,159,441 63.39%
Willard Mitt Romney Republican 2,401,799 36.61%
No third-party nominee won 1.27 of the total vote so those nominees are ignored.
The split is 20-9.
Florida (really close)
Barack H. Obama Democratic 4,237,756 50.44%
Willard Mitt Romney Republican 4,163,447 49.56%
The split of Florida is now 17-12 for Obama, which is vastly different from winning 29-0.
With the four largest states in electoral votes the total is now 87-64 under this system instead of 113-28 with a WTA system in place. With this method in place President Obama is down 26 electoral votes and Mitt Romney is up 26 from the reality of a WTA system. As it is the Electoral College gives a structural advantage to the Democratic nominee. Aside from Texas the five biggest states that President Obama lost were Georgia (16), North Carolina (15), Arizona (11), Indiana (11), and Tennessee (11). In contrast President Obama won Illinois (20), Pennsylvania (20), Ohio (18), Michigan (16), New Jersey (14), Virginia (13), Washington (12), and Massachusetts (11).
So let's see what offsets look like. Georgia and Michigan look obvious enough because the states have the same number of electoral votes and were decided by similar-but opposite margins:
Georgia
Willard Mitt Romney Republican 2,078,688 53.96%
Barack H. Obama Democratic 1,773,827 46.04%
Romney 10 - Obama 6
Michigan
Barack H. Obama Democratic 2,564,569 54.80%
Willard Mitt Romney Republican 2,115,256 45.20%
Obama 10 - Romney 6
Perfect! It was 16-16 in WTA reality between these two states.
I'm not saying that there are any other offsets that good.
Some whiz could probably calculate the effects of this system. It is still effectively WTA for a state with three electoral votes. No such state was close in 2012. Four? New Hampshire was the closest of them:
Barack H. Obama Democratic 369,561 52.83%
Willard Mitt Romney Republican 329,918 47.17%
One would have to get 50% of the relevant vote to win even one electoral vote in N3ew Hampshire or any other state with four electoral votes unless the state gets to allocate electoral votes in part by Congressional district as does Maine.
Five? Nebraska suggests itself because it allotted one electoral vote to President Obama in 2008.
Willard Mitt Romney Republican 475,064 61.13%
Barack H. Obama Democratic 302,081 38.87%
With five electoral votes a state would allocate one vote to the second-place finisher with so much as 1/3 of the total vote.
With six electoral votes, four allocated based on popular vote, some of the blowouts would not be WTA.
Utah illustrates the case:
Willard Mitt Romney Republican 740,600 72.62%
Barack H. Obama Democratic 251,813 24.69%
Gary Johnson Libertarian 12,572 1.23%
Ross C. 'Rocky' Anderson UT Justice 5,335 0.52%
Jill Stein Green 3,817 0.37%
Virgil H. Goode, Jr. Constitution 2,871 0.28%
Other (+) 2,807 0.28%
If the largely-irrelevant candidacies vanish as I put in the initial rules one gets this:
Willard Mitt Romney Republican 740,600 74.63%
Barack H. Obama Democratic 251,813 25.37%
and President Obama gets one electoral vote in Utah.
........
It might cause difficulties for news readers who can no longer say "Smith wins 11 electoral votes from the Indiana" at 7PM on Election Night because if the Democrat wins 44% of the popular vote in Indiana he will still get four electoral votes in Indiana. More likely the nature of our elections change so that (with the current patterns of voting) a Democrat is likely to seek out votes in places like El Paso, Dallas, San Antonio, Houston, Memphis, New Orleans, Atlanta, St. Louis, Kansas City, Omaha, and Indianapolis.
So what would be wrong with allocating electoral votes by district? I'd have no problem with Maine and Nebraska keeping their current systems due to a grandfather clause. Allocating votes based on the electoral college means that a State legislature could decide how that state votes by gerrymandering Congressional districts so that one Party has a built-in and rigid advantage. President Obama would have lost Michigan, Ohio, and Pennsylvania on that basis even though he won those three states by clear margins. Congressional districts have a transitory nature as it is.