Why This Affair Won't Be the End of Ensign

News of his affair with a campaign staffer won't force Nevada's GOP Sen. John Ensign out of office, predicts Nate Silver in FiveThirtyEight.com, even though he has frequently preached about the ethical lapses of others. A resignation by Ensign would prompt a special election in 2010, and Ensign's party is still struggling to find a good Republican candidate to take on Harry Reid that year, even though the Senate majority leader is considered vulnerable.

A special vote could make it tough for the GOP to keep the seat, or result in “a free pass” for Reid, Silver writes. Further, unpopularity isn't nearly as crippling to senators, as opposed to, say, governors, because senators “don't have to govern, or to preside over any legislature.” That's why Eliot Spitzer resigned in a heartbeat but David Vitter didn't, and why Roland Burris is still in the Senate. But resignation or no, the scandal offers Dems a chance “to play offense” for a key seat.