Many close aides had been lobbying for the low-risk, non-objectionable Pawlenty, arguing that the two could run as outsiders, taking on Washington…

Instead, Romney went for one of the most prominent faces in Washington. “Do no harm,” the campaign’s longtime philosophy about choosing a ticket mate, had suddenly become: “Let’s take a chance.” For several weeks, top aides had seen that Romney was learning toward bold over safe.

“Chemistry, seriousness, bigness,” said one of Romney’s closest advisers, when asked what sealed the deal for Ryan. “Win with a mandate to fix what needed to be fixed.”…

The campaign skipped only one obvious potential source of insight on the candidates: Romney aides say they did not conduct any polls or focus groups to see how the potential running mates might play with voters.