The strategy worked wonders two years ago when the remarks of Mr. Akin and Indiana U.S. Senate candidate Richard Mourdock not only squashed their dreams of being elected to the Senate, but also cast a pall over the party and made it harder for the Romney camp to stay on message.

“Akin was a distraction in the sense that the national press was focused on that controversy while we were looking to methodically drive an economic message in the closing days,” Mr. Madden said.

The outlook, though, for Democrats heading into the November election is grimmer than it was in 2012.