I'm at the airport in Charlotte, waiting to go home, and I've just realised I'll be on one of those small planes.

I hate these planes, and I think my pilot may still be in high school, so I'm going to try to focus on what we learned this week at the Democratic National Convention.

I said often during my live shots that this was likely the most important speech of President Barack Obama's political career. I'm not sure he delivered, but I'm also not sure he could have. As a candidate, you can talk in the abstract, about the ideas of hope and change. It's much harder to craft a speech when you also have to talk about your record.

As the president reminded us: "I'm no longer just a candidate. I'm the President."

I know what it means to send young Americans into battle, for I have held in my arms the mothers and fathers of those who didn't return. I've shared the pain of families who've lost their homes, and the frustration of workers who've lost their jobs. If the critics are right, that I've made all my decisions based on polls, then I must not be very good at reading them. And while I'm proud of what we've achieved together, I'm far more mindful of my own failings, knowing exactly what Lincoln meant when he said: 'I have been driven to my knees many times by the overwhelming conviction that I had no place else to go.'"

That to me was the most powerful moment of his speech. It summed up in simple terms what I think the underlying theme of this convention was: "Being President is hard, and no one could do it better." Gone are the days when so many believed that this one man could change the world - and no one single speech could bring that back.

What we got instead were plenty of shots at his opponent, basically the message was, "if you’re not thrilled with me, you are really going to hate the other guy". That is where the fear came in the next most memorable moment was all about mocking Mitt Romney. "After all, you don't call Russia our number one enemy – and not al Qaeda – unless you're still stuck in a Cold War time warp ... You might not be ready for diplomacy with Beijing if you can't visit the Olympics without insulting our closest ally."

It was a pretty clever line and it's probably good politics, but it somehow seemed beneath this president, who promised to elevate the discussion. That is what I took away from this speech it's what I've heard all around the country, that "the campaign is just not the same as 2008". I realise now, after the convention, those days are long gone. As Barack Obama said, he is no longer a candidate, he is the president - and he wants to keep his job.

Other key speeches: 

Vice President Joe Biden: 5 out of 10

I just kept thinking, as I watched: "He is just a better speaker than this." His job was to be the attack dog, and he tried to fulfil it. First, he tried to paint a picture of the president as courageous and compassionate. I'm not sure why they took this tack he never could have done a better job at humanising his boss than Michelle Obama did. I have to wonder why the campaign didn't use his knowledge of Washington to tell the audience about all the times the president tried to reach out to Republicans - only to be ignored. I think, if the country is disappointed in this administration, it is in large part because the tone has gotten worse, not better as promised. He could have blamed the Tea Party they aren't going to vote for him in any case, so why not point the blame?

Former President Bill Clinton: 8 out of 10

I had forgotten what it was like to watch Bill Clinton give a speech. As I watched him, I couldn't help but wonder why the campaign would put him up before the current president. He does it like so few others can. I followed along his prepared text and was simply amazed that he was just adlibbing most of his speech. The most memorable lines seemed to come off the top of his head, not the teleprompter. Who else can do that? The only flaw, in my opinion, was that it was just much too long. He made so many points, I couldn't help but think most of them were going to get lost. The one thing I think most will remember from the former president was his defence of President Obama - when he said that no-one could have fixed the economy in just four years.

Michelle Obama: 10 out of 10

Here is how I know that it was a good speech. When she spoke about her girls, and her voice cracked, even the cynic that I am instantly thought that she was conveying real emotion. She said much that was meant to make her husband seem like the rest of us, but what I took away from her speech was the underlying theme that she truly believes that he isn't in it for the glory, but for the greater good.

If that message got through to the electorate, it will be hard to erase with any number of nasty 30 second TV adverts.

Follow Patty Culhane on Twitter: @PattyCulhane