Ros Atkins presented the first part of the journey, travelling all the way from Los Angeles to Dallas.
Along the way, he stopped off in Tombstone, Arizona and Truth or Consequences in New Mexico.
Part 9: Moving north
I'm thinking about giving up my job at the BBC to start a TV series about Truth or Consequences.
For a New Mexico town of 6,000, there is a fair amount going on.
In our few hours in T or C I heard about a serial killer, S&M circles, and secret stashes of Nazi memorabilia.
I also heard that the post office is a great place to find love, how the now dead fire chief still remains in the job, and that the hot springs have magical healing powers.
If that's not enough for you, there's the film star Jack Black asking for - and getting - more water in the Rio Grande, a local resident who hasn't got out of bed since Christmas, and Deadheads for Obama - a group of Grateful Dead fans who are producing tie-dye Barack t-shirts.
The last bit I know is true. The rest I have no idea, but in a strange way, it doesn't matter.
I loved it there, with its Turtleback Mountain and crystal-clear light. Either way, a TV show about a town named after a radio show has a certain logic to it.
We have now moved north to Santa Fe, which is home to Governor Bill Richardson - who you may remember ran for President.
When he backed Barack Obama he criticised the negative tone of Hillary Clinton's campaign. So what about Obama now?
A study has shown his guys ran more critical ads than McCain's in the last week.
"Look - Barack is still a positive man with a positive message," the Governor told me.
"That's not changed, but politics gets negative at this stage."
The man he wants to be president seems to have realised this too.
The attack ads on TV are sharper and more frequent, and he's up in the latest poll.
But hold on - isn't McCain supposed to be in the box seat? Haven't we all been saying that Palin's put Obama on the back foot?
"Look," said Governor Richardson, with the air of a man who has seen a few elections, "there are 50 days to go. Believe me, this is the start not the finish."
I'm beginning to learn that he is right.
End of Section
Part 8: Truth - and consequences
I'm sitting on the brown banks of the Rio Grande, watching water of the same colour make its pedestrian progress towards the border town of El Paso and into Mexico.
This is Truth or Consequences - once a treasured game show on the radio here in the States, but now a town of 6,000 in New Mexico. The show wanted to find a place which would take its name, and in 1950 the then Hot Springs volunteered.
Twenty of so people joined us for our broadcast - sitting on fold-out chairs on a little shadeless patch of concrete by a bandstand.
Ten years ago, one of them, Dale - now in his 70s - had a heart by-pass which cost $159,000.
He went bankrupt trying to pay and seemed still furious that despite a life's worth of work, and four years in the military, he didn't get the help he needed. He wants a national health service.
The local pastor is a barrel-chested guy in his 50s with a check shirt and jeans. His wife became seriously ill last year and with no insurance to cover her healthcare, he too went bankrupt.
"Does that seem fair?" I asked him. "It's not your fault that she became ill."
"It's no-one else fault either," he solemnly replied. "Why should everyone else pay for my misfortune?" Almost half the group nodded.
Next was Eddie - a rancher with no insurance. "What if you break your leg on the way home? What if you get ill?" I asked him.
"I'll take my chances. I look after myself," he replied confidently. "I'd pay the money but the government would waste it."
And so the stories went on. Another lady went bankrupt after her parents had a car crash and she had to pick up the bills.
This is the richest country in the world - and to some it's extraordinary that so many people have their lives turned upside down by paying for healthcare, or not being able to.
But for a good percentage of people here, this is better than the tax-heavy communal alternative.
And you can't explain it by thinking people don't care about each other. This is all in a town which raised $17,000 to help a local man get treatment for cancer when the insurance wouldn't cover it.
It was a lesson in the fierce independence many Americans put above all else, even their own interests sometimes.
For them that independence is the truth, and the consequences.
End of Section
Part 7: Gunfight at the O.K. Corral
I'm writing this on the main street of Tombstone, Arizona. This is as far south as the Talking America bus is going to go.
The Mexican border is under 50 kilometres away.
It's desolate around here. Terracotta rocks and hills are sprinkled with low-lying scrub and a single highway into town is the only sign of life.
It is a small place, with saloons, boardwalks and signs written in the font you'll have seen in just about every western film.
Around 1500 people live here now, and when they turn on their televisions on to follow the election campaign they'll see a 21st century version of something their great- great- great -grandparents might have recognised.
Tombstone was founded in 1879 and despite the beautiful scenery doesn't sound like the kind of place you'd want to live.
In the 1880s it averaged 20 violent deaths a week. If you work that out per person living there, it makes it more dangerous that any peace-time city in the world now.
The disagreements, if we can call them that, went like this.
On one side there were the cowboys: freewheeling guys who'd settled down here once the trains had brought an end the Texas cattle drives.
And on the other were the businessmen from the north who'd travelled down to run the local mines.
And the way the two communicated most of the time seems to have been by shooting each other dead. Or at least trying to.
And if things were lively anyway, October 26 1881 was definitely a day to stay indoors.
Tombstone had a Republican mayor called John P Clum and he'd made his mind up to see the cowboys disarmed or driven out of town.
A local County Sheriff, Johnny Behan, was a Democrat.
It's not clear to be if he really approved of the cowboys, but they'd been on the same side during the civil war, so on this occasion he stood up for them.
What ensued became known as the Gunfight at the O.K. Corral.
It took place just across the road from where I'm sitting in a low-slung stables and backyard.
It took 30 seconds, three died and the Republicans won. Soon after the remaining cowboys left town, but they didn't leave their beliefs. Years later they'd return to renew the fight.
Of course you've got to be careful with your comparisons here, and it's definitely taking McCain or Obama more than 30 seconds to deliver a knock-out blow, but it does illustrate how long the passion of the two sides in American politics has burned.
And it's a good story to tell anyway.
One last thing to mention - on the way here was a police checkpoint, and 30 Mexicans sat on the tarmac under guard.
Illegal immigration is a massive issue here in the south-west and we're driving to New Mexico to discuss it.