CNN will host the latest Republican primary debate tomorrow at 8:00pm Eastern. It will be the candidates' last chance to debate before voting takes place in South Carolina on Saturday. The dynamics of the debate will be similar to the debate on Monday: Mitt Romney is a big favorite to win the nomination and enjoys a comfortable lead in South Carolina polls, and it's up to the other candidates to take him down. The media narrative continues to suggest that if Romney wins in South Carolina, it's all over.
But there is a twist: Newt Gingrich got positive reviews for his debate performance on Monday, and the polls show Gingrich with a substantial lead over Rick Santorum in both South Carolina and Florida. This week, Gingrich said publicly that he would like Santorum and Rick Perry to drop out of the race and endorse him so that the Anti-Romney vote can unite. Santorum and Perry may now be more aware of the fact that it's not enough to take down Romney--they must stop Gingrich, as well. Though Perry knows his own situation is hopeless, Santorum may come to realize that the biggest threat to Santorum is Gingrich, not Romney. If Santorum trails Gingrich by too much, his candidacy will lose all support. But he can survive if he's close enough to Gingrich, even if they both lose to Romney.
It will therefore be important for Santorum to go on the attack against Gingrich. Santorum needs to prove that Gingrich is not the only candidate who can put in a strong debate performance. So far, Gingrich has done well in answering questions, but tends to be a bit weaker when confronted by other candidates in a back-and-forth exchange. Still, as we have seen in previous debates, just because a strategy is optimal doesn't mean a candidate will actually follow it. Santorum may very well continue to attack Romney.
As for Romney, he will once again need to play the role of the gracious frontrunner who is undisturbed by the attacks against him. On Monday, he skillfully parried the attacks against Bain Capital and his history of flip-flopping. He was more hesitant when asked about his tax returns. Since that got some attention, his rivals will surely focus on the tax return issue in tomorrow's debate. Chris Christie, who endorsed Romney and has campaigned for him, has said publicly that he thinks Romney should release the returns. Will Romney be able to effectively answer whether he'll release his tax returns? Romney is undoubtedly preparing for this line of questioning. If Romney has decided that he won't release them, it will be difficult for him to explain why not, without leading voters to worry that he has something to hide.
Finally, Romney must decide whether he should attack Gingrich. Romney has usually preferred to remain positive during the debates, in the belief that as frontrunner the status quo is beneficial. However, Romney may feel threatened enough by Gingrich that if Gingrich attacks him first, he will unleash a counterattack.