In Boone, Iowa, Pete Buttigieg's campaign bus pulled up to the event space for his town hall. He stepped off his bus and strode right onto the stage.

"Well, that is a fun way to make an entrance," he said, smiling, with his 2020 PETE bus providing the backdrop for his campaign event.

BOONE, IOWA - SEPTEMBER 22: Democratic presidential candidate, South Bend, Indiana mayor Pete Buttigieg speaks during a campaign stop on September 22, 2019 in Boone, Iowa. Buttigieg is on the second day of a four-day bus trip around the state. / Getty Images

The South Bend, Indiana mayor rolled across Iowa on a four-day bus tour and allowed everything uttered on the bus to be on the record, drawing ready comparisons to the late Senator John McCain's "Straight Talk Express," the bus he toured the country in when he ran for president in 2000. The coach, which has also been around the country in the service of former President Barack Obama, Justin Timberlake and Tom Hanks, is now styled with Buttigieg signs, marble floors and plays news channels or football in the background.

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"It's a chance to do something different in terms of trying to get us all out of gaggle mode," Buttigieg said during the bus tour.

He and his campaign have ramped up spending in Iowa in the past month, releasing a new TV ad on Monday, hiring more staff on the ground and opening offices. He added that the strategy is not to "go around Iowa."

"We know that Iowa is where we can turn heads," he said. "I think even other early states will be looking to see what Iowa did."

Buttigieg recognizes that at this point in the election cycle, the large field makes it difficult to know what characterizes success, besides winning the Iowa caucuses.

"I think the thing is so fluid, including the expectations game, that we won't really know fully what success in February looks like until January," he predicted.

WEBSTER, IOWA - SEPTEMBER 22: Democratic presidential candidate, South Bend, Indiana mayor Pete Buttigieg speaks during a campaign stop at Twins Park on September 22, 2019 in Webster, Iowa. / Getty Images

The bus tour took place after a poll by the Des Moines Register and CNN showed that Buttigieg received 9% of support, which is a 6% drop in support from June. But on the upside, his favorability is up, rising 8 points from the June poll, and only 20 percent of likely Democratic caucus goers say they made up their mind on whom to support.

Buttigieg spoke admiringly of competitor Massachusetts Senator Elizabath Warren, who received the most support in the poll, and acknowledged her steady rise in polls.

"She has a good organization," he said. "There's a clear message, and it's about the things we really care about."

Buttigieg said he's been thinking of electability and providing counterarguments to President Trump's Democrat-labeling, including Mr. Trump's one-size-fits-all description of Democrats as socialist elites who are just part of the Washington establishment. Specifically, Buttigieg brought up his background as a Midwest mayor, his work with the private sector in South Bend and his military service.

"Pointing out that we can deflate his socialist argument, that we're immune to his Washington argument and that we absolutely welcome the commander-in-chief argument, I think it does help remind voters why I am best positioned to beat this president," Buttigieg said on the bus ride from Webster City to Iowa Falls.

DUBUQUE, IOWA - SEPTEMBER 23: Democratic presidential candidate, South Bend, Indiana mayor Pete Buttigieg speaks to reporters on his campaign bus on September 23, 2019 in Dubuque, Iowa. / Getty Images

Kristin Garnant, who saw Buttigieg in Clinton and has listed him in her top five, said the biggest thing she is looking for in a candidate is someone who can reckon with President Donald Trump and "not be belittled by him." She feels that Buttigieg has a chance and said she likes Buttigieg's executive experience and military experience.

"All of those things, that resonates across the country," she told CBS News.

On the bus and during events around Iowa, Buttigieg also talked about building a campaign around a "sense of belonging," and that included inviting Republicans to listen to his message. Buttigieg is aware that his measured tones differ from some of the other presidential candidates in the race, who he thinks talk down to voters.

"This kind of finger-wagging that tells people they've been foolishly voting against their own interests, I don't think really broadens the base," Buttigieg said. "We got to make sure that whatever reasons people had for being Republican over the years that we want them in our party."

Seventy-one-year-old Cathy Nelson, of Galena, Illinois, saw both Vermont Senator Bernie Sanders and Buttigieg in Dubuque and decided that she likes Buttigieg more. Buttigieg's message on climate change and gun control resonated with her. But she added that she is still looking for a candidate to support and expressed disdain toward Mr. Trump.

"I just don't agree with the guy that's in the office now. And he's not going to tell me he's the only one I can vote for because I can go Democrat. So, I am trying to listen to what all they are saying and what they are going to do," she said.

DUBUQUE, IOWA - SEPTEMBER 23: Democratic presidential candidate, South Bend, Indiana mayor Pete Buttigieg speaks during a campaign stop on September 23, 2019 in Dubuque, Iowa. Buttigieg is on this third day of a four-day bus trip around the state. / Getty Images

The youngest candidate in the race at 37 years of age, Buttigieg most often makes an argument that this election is one that calls for generational change. Some of the candidates running are twice his age. Buttigieg is urging Democrats across the country not to not play it "safe."

"The part of the electability debate that I'm really trying to turn on its head is the idea that you need the most stable, familiar face to be elected," he said. "Again I don't think we would be here if people liked what they were getting out of the establishment, which means sending in the establishment is a terrible way to try to win the election."

On one of the last legs of the trip, Buttigieg scanned the newest Monmouth University Poll, which showed that he received 10% of support from registered New Hampshire Democratic Party likely voters. Asked if the bus will be going from Iowa to Manchester, New Hampshire, Buttigieg responded, "I would not be shocked if the bus is making an appearance in New Hampshire, but I'll let the campaign work out the next steps."