Ever since 2004, when the G.O.P. fired up its conservative core by getting gay-marriage bans on the ballot in 11 states on Election Day, Democrats have sought their own rally-the-base issue. What could motivate liberals to turn out for November's midterms? They think they have an answer: the minimum wage.
The federal minimum wage has been stuck at $5.15 an hour since 1997. Polls show that more than 80% of Americans favor an increase, but most Republican politicians--who traditionally side with the business lobby on the issue--do not. So Democrats are sharpening their attacks on the G.O.P. for seeming out of step with public...