Quarterly statements are just coming in and most should have a decent increase this quarter. Does enough of the middle class have 401K plans where they could feel personal good economic news, which could help lend credence to the good (or improving) economic statistics on a national level of late (7.8, declining deficits, start of housing recovery, etc.).
Maybe it's wishful thinking, but I'd like to think some fence-sitters could be swayed by listening to all the truther crazy over the BLS stats for the last couple days and then seeing tangible evidence that things are improving. If there are enough people in this subset (people with 401Ks who only check them out when the quarterly statement comes in and who are undecided).