Senator John McCain chose Gov. Sarah Palin of Alaska as his running mate on Friday, shaking up the political world with a surprise pick at a time when his campaign has been trying to attract women, especially disaffected supporters of Senator Hillary Rodham Clinton.

In choosing Ms. Palin — a 44-year-old conservative Christian and self-described “hockey mom” who has been governor for less than two years — the McCain campaign reached far outside the Beltway in an election where the Democratic nominee, Senator Barack Obama, is running on a platform of change.

The pick, confirmed by Republicans familiar with the decision, amounted to a roll of the dice, a gamble that an infusion of new leadership — and the novelty of the Republican party’s first female candidate for vice president — would more than compensate for the risk that Ms. Palin could undercut one of (more...)