WASHINGTON–Sen. John McCain’s decision to pick Alaska Gov. Sarah Palin as his running mate will unquestionably shake up the race.

First and foremost, of course, the move will help McCain woo those coveted Hillary Clinton backers, who were so disappointed that the New York senator fell short of the nomination. Palin, a mother of five who is in her first term as governor of Alaska, could be a magnet for that disaffected, vital constituency.

Plus, she’s a Washington outsider, with a reputation as a reformer. And she will likely  short-circuit efforts by the Obama campaign to make inroads in Western states. The early talk on cable TV was about Palin’s taste for mooseburgers and guns.

On the other hand, of course, she’s young and has a fairly thin resume, which could hurt McCain’s efforts to tar Obama as unprepared for the White House. And who knows how she’ll fare in a debate against the sharp-elbowed agile Biden.

In any case, McCain’s surprise pick of Palin, and Obama’s choice of Sen. Joseph Biden, D-Del., is a mirror image in some ways of the 2000 campaign. Then, Texas Gov. George W. Bush, dogged by questions about his experience and gravitas, tapped veteran Washington hand Dick Cheney, ala Obama’s choice of the seasoned Biden.

Al Gore took the bold route, a la McCain this time, with an outside-the-box pick of Sen. Joseph Lieberman, D-Conn.