400 electoral votes are (almost) impossible under the circumstances mentioned above. Maybe in 2020 if Hillary is extremely popular. With a balanced budget, 3.5% GDP growth, more income equality and the lack of severe foreign problems.
But there is one path to 400+ electoral votes: With a strong third party run, that devides the votes of one party into two; simiular like it happened in 1912. Wilson received only 42% of the popular vote, but won 81% of the electoral vote.
Probably with one candidate from the Tea Party and another from the GOP estabishment.
A 2016 scenrio, although it's pretty unlikely to happen that soon:
Democratic: Hillary Clinton/Tim Kaine: 445 EV. (45%)
Republican: Jeb Bush/Chris Cristie: 76 EV. (30%)
Tea Party: Ted Cruz/Michele Bachman: 17 EV. (23%)
