Democrats are also faltering in two states they hoped to pick up. In Kentucky, Alison Lundergan Grimes declared on July 29 that, “The Iron Dome has been a big reason why Israel has been able to withstand the terrorists that have tried to tunnel their way in.” But Iron Dome is a missile defense system and useless against the tunnels built by Hamas. This adds to existing questions about her command of the issues.

In Georgia, Democrat Michelle Nunn suffered a self-inflicted wound when it turned out that in December her campaign posted online a 144-page strategy memo. It suggested that she came across as “a lightweight” and “not a real Georgian,” listing as weaknesses her support for ObamaCare and her vulnerability to being depicted as “a rubber stamp for Democrats.” And Georgia’s GOP runoff yielded a Republican, businessman David Perdue, who can win.

Nationally, Mr. Obama’s job approval rating remains dangerously low—41% in Wednesday’s Gallup tracking, 4% less than at this point in 2010. He is in worse shape on major issues. In the June 1 ABC News/Washington Post survey, the president’s approval rating on immigration is 38%, down 10 points from April 2009. An Aug. 3 NBC News/Wall Street Journal poll put his approval rating on foreign affairs at 36% and on the economy at 42%, both down from 56% shortly after his 2009 inauguration.