Mitt Romney walked away from last night’s Republican presidential debate unscathed. No other candidate delivered a serious challenge to his status as frontrunner, though there was plenty of shuffling in the ranks.

Newt Gingrich was the biggest surprise. Yesterday many people would be excused in thinking he had long since dropped out. But his attacks on the media put distance between his campaign’s disastrous start – which the press has used to shape the narrative of his bid – and the experienced, shrewd politician we saw last night. His answers proved he understands how to get things done in Washington; Something voters might be more open to following the dysfunction around the debt crisis. Gingrich made himself relevant again, and now we wait and see if he can take advantage.

On the other hand, Tim Pawlenty did serious damage to his candidacy. He was clearly on a do-or-die mission against Romney, but couldn’t evolve to the line of questioning that put him in a faceoff with Michelle Bachmann. The two spent considerable time rehashing long-past political battles from Minnesota, in which Pawlenty struggled to go beyond rehearsed and tired talking points (eg on taxes, “historic highs to historic lows”).

The main result of Pawlenty and Bachmann’s confrontation is that it took the heat off of Romney, an ideal outcome for the candidate who has kept him well above the fray of a day-to-day nomination battle.

Even though they were hoping for more attacks against Romney, Obama's team probably liked what they saw last night between Pawlenty and Bachmann since it alludes to a more divisive primary fight that reveals real divisions within the GOP, and creates wounds that over time become tough to heal.

There are reasons for Republicans to be pleased as well. Overall, the field is sharpening its line of attack against President Obama and becoming a more formidable group of challengers. As a group, they were much stronger on Thursday than in their last debate in June. It’s unlikely their arguments will evolve much further, however, so you can be sure the Obama campaign is preparing to deal with everything we heard.

But there’s one person who we didn’t hear from last night who will become increasingly relevant in the days and weeks to come. Rick Perry is rumored to announce his candidacy this weekend. He has appeal in both sides of the party, which makes him instantly competitive. The Tea Party sees him as one of their own, a guy who gets it on the small government, take no hostages approach while the establishment sees a charismatic, pragmatic, three term governor.

Pawlenty has been trying unsuccessfully to position himself in that way for months. So we have to wonder whether his disastrous performance last night along with Perry’s encroachment pushes him towards the off ramp.

More importantly, Perry’s addition could provide a more direct challenger to Romney for the nomination. Bret Baier was on to something when he began the debate by challenging Romney on his record of slashing jobs in this country. No other candidate followed through on what is definitely a weak spot for the frontrunner.

From everything I see of Perry, he doesn’t seem like the type of person to shy away from following through. That may be just what this field needs for a shake up.

Joe Trippi is a Fox News contributor and political strategist who worked for Ted Kennedy, Walter Mondale and Gary Hart and turned Howard Dean into an unlikely front runner in 2004. For more visit JoeTrippi.com.