Waterloo, Iowa — Less than a month from the Iowa caucuses, Joe Biden is continuing to overwhelmingly target rural communities throughout the state. In fact, the last event he held in Des Moines before his current bus tour was in November, when former Iowa Governor Tom Vilsack and wife Christie Vilsack, endorsed him. He is currently on day three of a six-day bus tour.

"We feel good about where this Iowa operation is and we feel good about where we are one month out," Biden campaign senior adviser Anita Dunn told CBS News, adding it's a "mistake" for campaigns to focus only on "larger population areas."

But the Biden campaign will be relying on ads to bring his message home in those areas, with $4 million in television and digital ads throughout the Des Moines, Cedar Rapids, Quad Cities and Sioux City areas. His campaign recently reportedly canceled ad spending in South Carolina between now and January 27, where he has been leading in recent polls. Campaign aides tell CBS News the strongest pockets of Biden's support in the state are in eastern Iowa, specifically the towns of Cedar Rapids, Davenport, Waterloo and Clinton.

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Biden's stump speech on the road continues to evolve as the week goes on, but three main topics have come into focus: bipartisanship, leading from Day One on the world stage and overcoming personal loss.

Bipartisanship and unity

Almost his entire stump speech now revolves around the character of the country — which he views as compassionate, decent and honest — traits he says are essential to unifying the country in a post-Trump administration.

He continues to rip into his Democratic rivals who bash bipartisanship and says the Constitution requires consensus. In an indirect indictment of his more progressive opponents, he says that those who don't respect the search for common ground wrongfully attack the "motives" of those who do seek consensus. He says in these mostly rural visits that the character of the country is strongest in communities like these.

Global experience

Biden's focus on foreign policy did not ramp up Friday with the news of the strike killing Iranian military commander Qassem Soleimani. Since the beginning of the campaign, Biden has said his experience on the world stage separates him from his Democratic rivals.

He says that he knows world leaders—and they know him, too. That includes Vladimir Putin and Kim Jong Un, Biden points out. In Iowa, Biden often connects his foreign policy experience with the trade war affecting rural agriculture communities. If the trope is that voters regularly do not place a premium on foreign policy, it is less true at Biden's events as they say this is points on the board for Biden even if they're debating other candidates.

On the killing of Iranian Gen. Qassem Soleimani, Biden on Friday said the U.S. is now on the "brink of a new kind of major conflict in the Middle East" and questioned whether President Donald Trump listened to his top military commanders when deciding to go forward and whether or not the administration has a plan for what comes next. On Saturday night, Biden ripped President Trump's tweets about Iran as "incredibly dangerous and irresponsible."

One contrast between Biden and his Democratic presidential rivals Sen. Bernie Sanders, Sen. Elizabeth Warren and Pete Buttigieg is the classification of Soleimani's killing as an "assassination" by the United States. Biden has not responded to at least 10 questions on Friday and Saturday from reporters about whether or not he agrees with this clarification.

Hardship

At the events throughout the country, it is hard to put into words the emotion that fills the room when Biden speaks about his family. The personal loss that Biden has endured, the tragic deaths of his first wife and young daughter and more recently of his elder son, are well known but still staggering to consider. Biden's most loyal backers in the state say this is what sets him apart from the rest of the field. Some candidates celebrate their large crowds or selfie lines, while Biden stands on the rope line connecting with every voter he can.

His pain has made him a figure of empathy for voters who also suffer. He tells them things will get better. This past week in Anamosa, Iowa, a woman rose to say she was humbled to spend her deceased son's birthday at the Biden event. There were tears in the audience as she spoke. Grown men and women cry throughout his events, moved by his life's commitment to the service of his country, even while grieving.

At the end of his stump speech, Biden often lapses into stories from his past, on topics ranging from climate change and education to healthcare, guns and foreign policy.

The events

Biden's events are on the smaller side, usually between 100 to 200 people. On Thursday Biden and Bernie Sanders both held events at the same location in Anamosa — the National Motorcycle Museum — and Sanders attracted about 200 more attendees. Biden isn't holding large-venue events of 1,000 or more, like some candidates. But on Saturday night in Des Moines, some 700 people packed a school gym to listen to him speak.

The attendees are generally elderly, with most looking more like Biden's generation and older, compared to Buttigieg's. His attendees sit quietly and sometimes clap and cheer when they hear something they like. It may not be raucous, but what shouldn't be overlooked is that the audience is actively listening. They're nodding their heads, whispering to their friends, and wiping away tears.

It's clear he's persuading some Democrats.

Ron Orf (left) and Janet Orf (center) pose for picture with former Vice President Joe Biden (center) and Rep. Abby Finkenauer (right), who endorsed Biden this week. The Orfs both say they recently decided to support Biden in the Iowa caucuses. CBS News / Bo Erickson

"I was vacillating between Biden and Buttigieg and I decided after [this event] I will go for Biden," Janet Orf, 71, told CBS News in Waterloo. "I was looking to see if his age was going to be a problem, and I didn't see it today. Even if it was he will put people in his cabinet that are smart and he will listen to them." Orf's husband, Ron, said he chose last week to support Biden over Buttigieg, as well.

The endorsements

Biden's campaign has also been touting his endorsements in Iowa. In their past three rural bus tours in December, former Governor Tom Vilsack and his wife, Christie, attended almost every one. Tom Vilsack, the highest-profile Democrat in Iowa, closed his events and brought the house down. Voters say the Vilsacks' endorsement is a huge draw. They describe Tom Vilsack the same way they describe Biden — as "a good man."

The other two major endorsements here are former Secretary of State John Kerry and 2004 Democratic caucus winner — a big draw to political watchers here in the state. He also boosts Biden's messaging on foreign policy. And finally, Representative Abby Finkenauer, who is traveling with Biden throughout her district and the adjacent ones, represents a push to bring in younger voters, a cohort which polling indicates is Biden's weak spot. Her conservative district is one of the Obama districts that voted for Donald Trump in 2016. The Biden campaign hopes her endorsement boosts Biden's message for bipartisanship and capturing "swing" voters.

Next week, a "We Know Joe" bus tour will launch with Kerry and a large group of congressional members mostly from the Congressional Black and Hispanic Caucuses. Biden has 30 congressional endorsements: 25 House members and five senators. Campaign aides say this is an effort to continue to project Biden's electability going forward in the more diverse primary states.