Perry, Iowa — At 77, Joe Biden would be the oldest person elected president, and Pete Buttigieg, who turns 38 next month, would be the youngest. Yet in Iowa, where the first contest of the Democratic primary will be held in February, the two Democratic hopefuls are locked in a dogfight for senior citizens, a pivotal demographic given their high turnout rate.

Older voters head to the polls with much greater regularity than other Americans. And nationwide, CBS News polling shows Biden's consistent lead is boosted by elderly voters, with 39% of voters 65 or older picking Biden, his largest coalition of support.

But in Iowa, statewide polls indicate Buttigieg has also captured the imagination of older voters. The fresh-faced millennial mayor of South Bend has made wooing older voters a priority, vowing to protect Social Security and promising a "Gray New Deal" for seniors.

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Last month, a Des Moines Register poll found Buttigieg leading in the state among likely caucus goers. It also found that he was the top pick of the 65-and-over crowd, outpacing Biden among a constituency he had dominated earlier in the race.

Buttigieg's strategy makes sense. Almost 80 percent of Iowans age 65 and older who were registered to vote in the 2018 midterm election did so, making up almost a whopping third of all votes cast, according to the Iowa Secretary of State's office. And while much of the focus in the 2018 midterm elections was on the higher-than-average turnout of young voters, older voters increased at similar levels.

While Buttigieg courts these older voters, the Biden campaign says it's not concentrating on any one voting bloc, although it plans to "more aggressively" engage with Iowa seniors.

Asked if Buttigieg's support among older voters might chip away at his own standing with seniors, Biden replied, "I haven't seen it so far, but maybe." He added that he thought Buttigieg was an "attractive" candidate but one who "hasn't cut it—anything—nationally."

OTTUMWA, IOWA - DECEMBER 21: Democratic presidential candidate former vice president Joe Biden speaks to guests during a campaign stop at the Hotel Ottumwa on December 21, 2019 in Ottumwa, Iowa. Scott Olson / Getty Images

Some observers say Biden's recent heavy campaigning in Iowa, including a recent eight-day swing, indicates his campaign may feel more threatened by Buttigieg's appeal to seniors than Biden is willing to admit. "I think he does have some more elderly support" compared to rivals, Clay County Democratic Chair Ryan Odor told CBS News after attending a recent Biden event in the county.

At the same time, Odor warned that Biden is playing catch up with older voters he assumed would win. "I think he rested on that for awhile and is recognizing that some of this support is starting to go elsewhere."

"I was scoping the crowd out and I noticed a few students, but a majority seem a little older," educator Heidi Larsen, 58, said in Storm Lake. "Well, I tell ya, a little bit older crowd but very enthusiastic," former coach Ted Bieth, 67, said in Mason City.

Even at events geared toward younger voters, like a late morning town hall at Iowa State University, only about 20 hands went up when Biden asked students in the crowd of more than 325 to identify themselves.

Then again, retirees are often overrepresented at nearly every candidate's events for a simple reason: They tend to have more time on their hands, especially on weekdays.

"[The students] I suspect are busy with classes, and so, its retired folks like myself who are in the best position to be able to attend," former state government lawyer Richard Mull, 67, said, taking advantage of the luxury of time older voters have to devote to political events.

This luxury of time also plays well on caucus night when older voters, who have off have fewer constraints than full-time workers or the parents of young children, can spend hours in the rec halls and high school gymnasiums where the caucuses occur.

"They stick and stay," Blackhawk County Democrats Chairwoman Vikki Brown told CBS News about older voters. "They are going to be out there caucusing...when some others may fail to be there." After attending a Biden event in Waterloo, Brown said Biden has "not only a higher ratio of black older voters but also older white voters" compared to his rivals.

"Don't doubt the Baby Boomers," Brown said.

While both candidates focus on policies specifically targeted toward seniors, Biden also relies on his old-school, retail-politician charm when courting the elderly.

When faced with a question from a woman in his approximate age bracket, it's not unusual for Biden to refer to her as "young woman" or "young lady." He also talks about how he, too, can have trouble understanding new technology, and relies on his granddaughters to explain why those Russian "bots" are attacking him online.

He commiserates by rhetorically asking how his critics can call him both too old and too naïve. "I thought with age came a little wisdom?" he says to laughter from supporters, many of whom say they feel defensive of Biden and his age.

"He can't be too old," lifelong Democrat Mary Rose Brown told CBS News. "I'm 94 and I'm still campaigning!"

And Biden's foreign policy credentials are also appealing to older voters, according Dallas County Democratic Chair Bryce Smith, who this weekend endorsed Senator Cory Booker.

"I think our foreign affairs are deeply concerning…especially to older people who lived through the tail-end of World War II and the Cold War and even the beginnings in the Middle East," Smith said. When touring rural Iowa, Biden will often criticize President Trump's trade policy, saying that it hurts the state's struggling agricultural sector.

Smith, who is 27, said that Biden is also able to connect with voters "like my grandmother" by embracing "the sense of urgency that a lot of the older generation...think we just need someone in [the White House] to stop the bleeding and...let us get back to some normal-ness."

Alice Krapfl, 88, expressed the same sentiment to CBS News.

"I want my grandchildren to be able to have a nation that we are proud of and we are not going to be too proud with that man who is in [the White House] now."

Voters in Perry were able to compare Buttigieg and Biden in back-to-back events this past weekend, since they held events in town just hours apart. Five undecided voters told CBS News these two men were their top two choices before the events.

After seeing both Biden and Buttigieg, all five said they were going home still undecided.