Rep. Nancy Pelosi (D-Calif.), facing a challenge from Rep. Tim Ryan (D-Ohio), is seen as the heavy favorite in elections on Wednesday to keep her top leadership spot, where she's been perched for the past 14 years. 

Democrats will decide on their new leader in a secret ballot vote that highlights the caucus's restlessness and resurrects internal tensions that have simmered since Democrats lost control of the lower chamber in 2010.

While House Democrats gained at least six seats this cycle — several contests remain too close to call — that figure was a far cry from the 25 pickups Pelosi had predicted. Seeking more accountability for the dismal results, dozens of restive lawmakers successfully delayed the party's leadership elections to this week to allow more time for reckoning. But in the eyes of Ryan and his supporters, nothing short of a change at the top will get the party back on a winning track.