Tierney, in his eighth term, won reelection in 2010 by a comfortable 57 percent, but GOP leaders have their sights on him this year as legal troubles have dogged his wife. In addition, GOP challenger Richard Tisei, a 26-year veteran of the Massachusetts state house, is seen as a stronger challenger than in past years.

Still, the Cook Political Report, an election handicapper, is predicting Tierney will "likely" see a ninth term.

Keating is in safer waters. The freshman Democrat is running in a newly created district, and already has a tremendous cash advantage over both his Democratic primary opponent and his GOP challenger.

The Cook Political report does not deem Keating threatened at this point in the campaign.