Call it channeling his "Inner Rosie."
San Antonio mayor Julian Castro has more "fire in the belly" than even some of his strongest supporters thought he did.
Whatever you think of Julian Castro or his politics, he definitely surprised a lot of people with his sometimes fiery, sometimes emotional speech at the Democratic National Convention Tuesday night.
I was in that Time Warner Arena watching it live, so I don't know how it played on TV, but the crowd in Charlotte definitely got what they were hoping and waiting for. After all, the build-up and hype had been huge. The comparisons daunting. Who could live up to the comparison to a young Barack Obama whose 2004 keynote address at a Democratic National Convention launched him into the Presidential Arena.
Castro had been rehearsing and tweaking the speech for weeks, trading drafts back and forth with advisors and even practicing with a teleprompter set up in a San Antonio hotel.
All the while he's also been talking to the media in the much more mild-mannered tone he's known for in San Antonio. Some quietly wondered is this the guy to bring down the house? Really?
So even somebody who has covered and known him for years was a little taken aback by his oratorical skills.
Before the speech he told me he nearly had it memorized. And an aide told me that once he got comfortable with the setting in the hall, he relaxed.
And Tuesday night it showed. Maybe he channeled the passion of his mom, Rosie, the driven, long-time activist who took her sons blcockwalking for candidates and causes she believed in since they were young children. They absorbed politics.
Or maybe he just let loose his inner Julian, the Julian I saw glimpses of when I moderated a mayoral debate he was involved in years ago.
He was up against the much-older, seasoned veteran Phil Hardberger and the sparks between the two sharp lawyers were fun to watch. Both smart. Both passionate. Both Democrat. But in the non-partisan politics of the city government of San Antonio, it didn't matter. They were both running for the same office and it was a fight. Two lawyers in a fight can get a little combative.
And they did. That night I saw more passion and fire in Julian than I've seen... until tonight.
Not long after that debate, Phil Hardberger won the election and became San Antonio's Mayor. But four years later, when term-limits forced Hardberger to retire, Julian took over.
And the speculation hasn't stopped about his future. Now it's exploded.
After the speech one of his aides told me that when Julian came offstage his reaction was almost stoic - something like "Did I do it?"
The answer in the hall was a resounding yes.
The questions now -- what does it mean and what's next?
First, tune in to more interviews with national news media as they dissect his speech and work on their comparisons. Was Julian like Barack?
Did he match up with Marco Rubio?
At 37 years old, Julian Castro has a lot of time left to answer all the questions.