In the event of no EC majority, 58 House members could decide the election

[Del Tachi]

In the event that no candidate wins a majority of electoral votes, the election is decided by the House of Representatives.  In the House, members vote as a delegation from the state they are representing.  While it has never been seen before for obvious reasons, one could assume that a candidate would only have to receive a majority of any particular state's House delegation in order to "win" the entire state.  Whichever candidate wins the majority (or 26) of state delegations is elected President.

Assuming that all of the above is correct, it would only take 58 members of the House of Representatives to deliver a majority of state delegations in the event of no Electoral College majority. 

These 58 members would be:

1) The whole delegations of the states of Alaska, Idaho, Wyoming, Montana, North Dakota, South Dakota, Vermont, New Hampshire, Maine, Rhode Island, and Delaware; 

2) A simple majority of the delegations of the states of Hawaii, Oregon, Nevada, Utah, New Mexico, Nebraska, Kansas, Oklahoma, Iowa, Arkansas, Mississippi, Kentucky, West Virginia, South Carolina, and Connecticut. 

While only comprising 13.3% of House membership, these representatives compromise the 26-state majority needed to elect a President.

A scenario like the one mentioned above is certainly very unlikely to happen, but it could make for good fiction.  For example, in the event of a three-way tie in the Electoral College with an independent of third party candidate costing the two major an Electoral College majority, the third-place candidate could attempt to consolidate support from the 58 members that could (if they coalesced) determine the outcome of the election. 

This would be very undemocratic, however, and I seriously doubt that an attempt to do this would not be countered by severe civil disorder.