We will eventually have a Democratic president who oversees disastrous economic times and/or an unpopular war, and there will be a realignment due to the self-correcting nature of our politics.
There wasn't a realignment in 2008 when Bush presided over both.
The national popular vote swung Democratic by 9.6 points, and Democrats picked up 113 electoral votes by flipping nine states plus NE-02. That's pretty significant.
I don't know how reliable the Atlas considers Wikipedia, but 2008 is listed as a "possible modern realigning election" on the page about realigning elections.