Everyone has known someone with a little Chihuahua, Shitzu or Pekinese that struts around acting like it’s a Great Dane. These little pups are convinced they can run with the big dogs. Attitude is in their DNA. Sen. Joseph Biden (D-Del.) is helping me see that politics also has some Pekinese pooches with a distorted perception of their size and strength.

In politics, it’s always puzzled me how most Chihuahuas and Shitzus correctly perceive that they are mere Congressmen and Senators while a few of their colleagues, similar-sized Pekinese, start thinking they are big enough to eat their Dog Chow in the White House Mess. What accounts for the disparity in their self-perceptions?

Rather than labeling Pekinese cockiness as “attitude,” the way we do with dogs, in politics we might clinically describe perceptual distortions as a by-product of high self-esteem. But because most all politicians have a robust sense of self-worth, it’s hard to figure why one diminutive dog like Joe Biden decides he’s ready to be president when so few other well-esteemed colleagues ever even dream of bedding down in the Oval Office.

Joe Biden was first elected to the Senate in 1972. So perhaps he thinks his exceptional seniority separates him from the pack. But New Mexico’s Pete Domenici was elected the same year and he’s not delusional enough to think the Westminster Kennel Club’s America needs his leadership. He’s satisfied to be the first Republican in 38 years in New Mexico to be elected to U.S. Senate, the first New Mexican elected to serve six full six-year terms in the Senate, and the individual who has served longer in the U.S. Senate than any other New Mexican in history. Despite all those “firsts” and record-setting accomplishments, Domenici doesn’t have an exaggerated sense of self-worth that drives him to prowl around looking for a bigger bone to gnaw on.

The key to understanding why some candidates misjudge their true size and potential may lie in state cultures. Biden hails from a tiny state that doesn’t know it’s small. Delaware’s official motto, “It’s great to be first,” says it all. Because someone several hundred years ago got their paperwork done first, “First State” politicians like Biden believe they’re forevermore going to be ushered to the front of the line in national competition. Compare that arrogance with New Mexico’s modest motto: We grow as we go! New Mexicans feel they’ll be lucky to get even what they earn.

Delaware’s unusually high self-esteem may be a danger to Biden. In fact, social scientists have shown that persons with the highest self-esteem also systematically exhibit the least self-control. High self-esteem has also been linked to narcissism. Just go to the mall and look for the kids whose parents have endowed them with the highest self-esteem and observe what happens when someone denies the child any whim. All hell breaks loose. That’s where Joe Biden is today. He can’t figure out why everyone’s second-guessing his remarks about Sen. Barack Obama (D-Ill.). Woof, I’m from Delaware, and I’m ready to run, so get out of my way.

Biden might take a lesson from Senate colleague Sam Brownback (R-Kan.) about running for president from a state that’s small in size but high in self-esteem. On a per-capita basis, Kansas has real bona fides in presidential politics, certainly better than Delaware’s. Dwight Eisenhower won Best in Show twice, and Alf Landon and Bob Dole won Best of Breed in the GOP competition. Even one-time presidential candidate Sen. Arlen Specter (R-Pa.) was whelped in Kansas. Yet a well-trained Brownback behaves like someone who knows he’s not yet running with the big dogs. He’s still on the porch. But Brownback’s demeanor is likely to give him a real run before this competition is over. Meanwhile, Biden will continue chasing his own little tail.

Hill is director of Hill Research Consultants, a Texas-based firm that has polled for GOP candidates and causes since 1988.