The GOP lost seats in the last gov't shutdown, but that was in 1995-96, during a Presidential campaign. The memories were still fresh with voters that time around and they payed the price for their actions. This time around they at least remembered not to repeat that timing. The debt limit was extended in 2011 for two years to avoid an election year battle, and we are currently more than a year away from the next midterms, a political eternity.
The question is this: would the GOP have been strong enough in their conviction to wage this fight if they thought voters were watching closely? Or was part of their plan to have some wiggle room before the next election?