Possibly there may be a chance if the composition of the blue voter base is weighted more toward retired FDR/JFK devotees and less toward the younger ethnic base.
The 19th District has two largely Democrat groups who are disillusioned with Obama: 1) Retiree/older voters and 2) Jewish voters. Both groups nation wide are off the liberal reservation and are very amenable to fiscal and international conservatism now. Furthermore, this is a special GENERAL election on April 13 guaranteeing low turnout, PLUS many snow bird voters have flown back north by now and are not getting much news about this election in their northeastern cities.
This is not even taking into consideration the strong Florida east coast Tea Partiers who remember it was Lynch who sued Wexler to make him prove residency in the State of Florida, let alone the 19th District. The court refused to dismiss the suit and Wexler, his goose being cooked, resigned in humiliation a few months ago.
This is an imminently winnable pick-up for the GOP. Any Free Republic posters, who are self-hating, so-called conservatives and who love to whine about how we cannot win, keep your fatalistic defeatism to yourself or go post it over at HuPo.