By the post-1980s standards, it would be a Republican carrying 41 states (minimum) and a Democrat winning 33 states (minimum).
The Republicans have averaged, at best, 9 electoral votes per carried state; and that's with the two elections of George W. Bush. The Democrats have averaged between 11 and 13 electoral votes, per carried state, with losing and winning candidates.
On the Republican side: Take George W. Bush's combined maps of 2000 and 2004. That's 32 individual states. (Bush won 30 and 31 states, respectively, in 2000 and 2004. He carried New Hampshire in 2000; lost it but flipped Iowa and New Mexico in 2004.) And nine more would come: Illinois, Maine, Michigan, Minnesota, New Jersey, Oregon, Pennsylvania, Washington, and Wisconsin.
Total (latest allocation)
409 electoral votes.
On the Democratic side: Take the 28 states, plus Nebraska's 2nd Congressional District and District of Columbia, carried in 2008 by Barack Obama. And five more would come: Arizona, Georgia, Indiana, Missouri, and Montana. That would actually add up to 399 electoral votes. (They were over 400 in the 2000s.) To officially reach 400, one more state (because of its recent close margins spread to Georgia) I would envision is: South Carolina. That would be 34 states. Total (latest allocation) 408 electoral votes.
