Peter is, I believe, the biblical figure with whom any given twenty-first century North American Christian resonates most, if they've given it any thought.
Faithful Old Testament figures lived a faith experience different to some degree or another, simply by virtue of the Holy Spirit's operation under the Old Covenant (see James Hamilton's excellent book on that topic, although I'm not certain I agree wholeheartedly with all of his conclusions). Adam was created, not born. Enoch walked with God and was no more. David is a tempting candidate, but we probably shouldn't attempt psychological contortions to relate to the second-most successful king of Israel. As for Job…no, let's not even go there.
Turning to the New Testament, Jesus is right out of the running, of course. While we do have a high priest that sympathizes with us (Heb 4:15) because he endured the hardships of life on earth, we cannot sympathize with his complete sinlessness, his utter desolation on the cross, or his resurrection experience – yet (and the "yet" is crucial, but a topic for another post altogether).
Likewise, relating to Paul is out of reach for most of us because we have not experienced a blinding flash of light from heaven, accompanied by the voice of Jesus. Nor have we received surpassingly great revelations and visions (2 Cor 12:2-7), and Paul's multiple apostolic journeys are the stuff of legend – and I'm not including the mythological (in the “fabulous" and "unsubstantiated" sense) final missionary trip to Spain.
Then there are the other disciples, of whom even John and James the brother of Jesus are not developed in detail by objective accounts (i.e., in the gospels and Acts) sufficient to render them fully relatable. Besides, John experienced the vision catalogued in the Book of Revelation – enough said. Now we merely relate in part..
So it's down to Peter. As so many preachers delight to inform us, Peter could be dunderheaded. But I insist he wasn't a dunderhead by character. For instance, many translations render Acts 4:13 more pejoratively than the original text warrants. Obviously, Peter was "uneducated" – in the sense that he had not studied under the Rabbis but was nevertheless preaching with authority. Uneducated, then, like someone with a high school diploma. Obviously, as a Galilean fisherman Peter was "common" – in the sense of lacking special rhetorical skills training, specially reserved in the first-century Mediterranean world for scions of middle- to upper-class families. Then again, Peter may not have received rabbinical training, but he had sat under John the Baptist's teaching, that wilderness dweller of whom Jesus said there was no one greater born of a woman (Luke 7:28).
Peter is therefore our biblical paragon of normality, attempting to advance his own agenda far too aggressively at times (John 18:10) and failing to live up to his calling as a Christ follower at other times (Luke 13:38). In the gospels and in Acts, Peter is drawn with colors and textures that allow the reader to see themselves in the variegation of this disciple's character.
Take heart then, for Peter was arguably the closest of disciples to his Lord and Savior (John 21:17), and it is in the character of Peter that we see our own normal human colors shine most brightly and fade to black most chillingly. Peter is Everyman.