Maverick maverick maverick
There's an idea that if you hit someone over the head with something over and over and over it will stick. And if John McCain keeps calling himself a 'maverick' (nevermind voting with Bush more than 90% of the time) most of the traditional media will keep going with it.
And so it was with the VP pick, as FAIR nicely lays out. While McCain was reportedly very close to picking Lieberman, he instead went with someone that is conservative on nearly every issue. That's energizing the conservative base. And that's not mavericking we can believe in.
While some print media use the term "maverick image" or some other construction to not say "McCain is a maverick" outright, the Washington Post had no such qualms. As they had it, "Fellow Maverick Survived McCain's Thorough Vetting Process, Aides Say."