Barberís best political asset is his team, many of whom used to run Gabrielle Giffordsí campaigns.
Primary season has just begun in earnest, but itís already clear it will take a toll on this Congress.
Exactly six months before Election Day, half of the members on this list face foes from within their own party.
Every name on this list has a 50 percent chance ó or more ó of not returning to Congress next year. To compose this regular feature, Roll Callís Politics Team examines every aspect of a memberís re-election prospects: district composition, campaign operation, fundraising, quality of opponent and recent performance.
Another incumbent to watch is Rep. John Conyers Jr., who could easily make this list if he is forced to run a write-in campaign or seek office as an independent ó the Michigan Democrat may have insufficient signatures to get on the primary ballot.
The following vulnerable members are listed in alphabetical order.
Heís a wanted man: This freshman has challenges from the left and the right in the 11th District.
His GOP opponent and top competition, attorney David Trott, first hit the television airwaves months before the Aug. 5 primary. Democrats vying for the nod include former State Department adviser Bobby McKenzie and wealthy urologist Anil Kumar.
So far, Bentivolio hasnít accumulated the means to fend off two rounds of attacks. He banked $129,000 after the first quarter ó just 7 percent of his opponentsí combined cash.
Vice President Joe Biden waits to conduct a mock swearing-in ceremony with Sen. Brian Schatz, D-Hawaii, in the Capitol's Old Senate Chamber, December 2, 2014. Schatz was sworn in to serve the remainder of his term since he was appointed to the seat after Sen. Daniel Inouye, D-Hawaii, passed away.