This has concerned me as well. What do they do if they don't take over the House and Senate? What if they don't even gain seats, overall, or only a couple in both houses? I think that they melt down and break up as a party into much more narrowly focused and competing groups, such as the "progressive Democrats" versus the "Democrat Leadership Council" types.
But continuing the analogy to Obrador's supporters, who have been trying to occupy the city of Oaxaca (with the idea of breaking away?), what would the moonbats do in this country that is analogous? Occupy Berkeley? They've occupied Berkeley since 1969. Who cares?
IIRC, one of the measures on the ballot out in Berekley, is whether to impeach President Bush...so I think they are ready to secede right now....LOL