Remember hearing those statements repeated over and over again by David Schweikert's opponents in the primary? They're eating their words now. Not only did David beat Harry Mitchell, he trounced him 52% to 42%. Abraham Lincoln lost elections eight times. What if no one had given him a chance because he'd lost before? If I had to guess, I bet around 1/3 of all politicians lose their first election, and 1/4 lose two or more elections. Voters are fickle, and if you run in an anti-Republican incumbent year, it doesn't matter who you are, you can lose. And if someone famous jumps into the race (like JD Hayworth did when David first ran in 1994, or how Ben Quayle did this year in CD3), that can also trump a great candidate.
It was a Republican year, but Harry Mitchell made it worse for himself by running one of the meanest, dirtiest campaigns in the country. His smear ads against David even made the New York Times, Politico and other mainstream national news sources. When your ads are so vicious that national media is spotlighting them, they are going to backfire. If Mitchell had kept his campaign clean, he might have had a chance at retaining his seat. He had a reputation as the nice grandpa from Tempe, which is why voters like him, but the ads destroyed it. Lesson learned? Don't spread lies so unfounded about your opponent that the story becomes how bad your ads are. David kept his campaign on the up and up and it resonated with voters, who turn off at some point to smear campaigns.