This has been making the rounds (and by that I mean "I came across it once through no effort of my own):

Via Ben Domench.
This is assuming a strong Romney showing—here he gets Florida, Ohio, New Hampshire, Nevada, North Carolina and Iowa—with Obama still eeking out Virginia, Michigan, Wisconsin, New Mexico, Pennslyvania and Colorado. In other words, a swing state split.
RCP's Erin McPike breaks down the numbers:
The most likely combination that would produce such a result requires Mitt Romney to carry all the states John McCain won in 2008, which after the redistricting process account for 180 electoral votes. Add to Romney's column Indiana (11), Virginia (13), North Carolina (15), Florida (29), Ohio (18), and New Hampshire (4). That would yield 270 electoral votes for Romney to 268 for President Obama, the narrowest possible win for the challenger.
But then subtract from the Republican ticket the single electoral vote Obama won in Nebraska due to the anamolous way the Cornhusker State allocates its five electoral votes, and there would be a rare electoral tie that would send the election to the House of Representatives.
There are other avenues to an electoral tie, as well, and given shifting dynamics and poll numbers, they aren't as unlikely as one might think.
For the sake of projections, consider Indiana lost for the president and give it to Romney (191). Add to his column North Carolina (15), Florida (29) and Ohio (18), getting the GOP challenger to 253. Then throw in Iowa (6), where Romney has been campaigning vigorously and where poll numbers are tight, getting him to 259. Add in Wisconsin (10), where Republicans are newly energized, and -- presto! -- Romney gets to 269.
Been a long time since civics class. What happens in a tie? First to kick a field goal? Penalty shots? Liberals' new best friend / old worst enemy?
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