Michael Barone delves into more polling data for his latest Washington Examiner analysis of 2014 election contests.

The precarious position of Democrats in their battle to hold onto a Senate majority has been further underlined in the recent Senate race polls conducted by Republican firm Harper Polling for the pro-Republican group American Crossroads.

Those show Republicans leading in four Democratic-held seats in states that gave Mitt Romney significant margins — Mead Treadwell 47 percent to 41 percent over incumbent Mark Begich in Alaska; Tom Cotton 42-36 over incumbent Mark Pryor in Arkansas; Bill Cassidy 45-44 over incumbent Mary Landrieu in Louisiana (even though 46 percent said they are not sure of their opinion of Cassidy); and Steve Daines 43-29 over John Walsh (appointed to the Senate on Friday to replace Max Baucus).

In target states, Harper had former Secretary of State Terri Lynn Land 42-37 over Rep. Gary Peters in Michigan; state House Speaker Thom Tillis tied 44-44 with incumbent Kay Hagan in North Carolina; and incumbent Jeanne Shaheen 40-35 over former Sen. Scott Brown. It’s a sign of trouble for an incumbent when he or she runs under 50 percent in a state, and it’s a sign of very serious trouble when an incumbent is running behind a challenger, as Begich, Pryor and (by a statistically insignificant 1 percent) Landrieu are in these polls.

The following table shows for each state Obama’s percent of the vote in 2012, his 2014 approval percentage in the Harper poll, the difference between them and the Harper 2014 pairings referred to above.

baronechart