James Crabtree in Prospect Magazine:
Although the Republican implosion was the main reason for the Democrat landslide, Pelosi deserves partial credit for the result. First, she instilled discipline. An old American bumper sticker joke is “I’m not a member of a political organisation. I’m a Democrat.” Pelosi has gone some way to squashing this stereotype. A study by Congressional Quarterly showed Democrats at their most united for 50 years. She has achieved this unity at least partly by frightening her party into line. Under her leadership, Democrats might not land many blows, but they make far fewer mistakes.
Second, she achieved the near impossible task of uniting her party on Iraq. The war presented Pelosi with a dilemma. She voted against it. But her lack of credibility on military matters meant that she could not argue for withdrawal without playing into Republican hands. She cleverly got around this by using Congressman John Murtha, a decorated Vietnam veteran, to make the case for withdrawal. She also managed to hammer out an uneasy truce among her colleagues. Democrats would go into the election arguing for “strategic redeployment.” The policy was close to meaningless. But when Iraq began to deteriorate over the summer, Democrats were just unified enough to take advantage.
Third, Pelosi successfully denied the Republicans victories.
More here.