Delaying the mandate helps democrat reelection chances because the people won't feel the pain prior to Nov. 2014. It's stupid for republicans to push for this.
You are forgetting that both parties are in this together. GOP wants this so they can help their fellow dems and keep the D.C. political class in-tact.
Stronger dems in red states means there is a lesser chance of a tea party or non establishment stooge candidate winning that seat instead.
GOP would rather a dem win the seat than a limited government conservative, so this is why they are trying to help them out.