Fact in focus: Since 1974, all 132 incumbents in US House races in Tennessee have won.

Fact in focus: In 2008, incumbents won 31 of Texas' 32 US House seats -- the average victory margin was 49%.

Fact in focus: Rhode Island Republicans regularly win a third of the state's US House vote, but have won no seats since 1992.

Fact in focus: No US House incumbent has lost in South Dakota since 1982. 

Fact in focus: US House races in Oregon in 2008 were won on average by a whopping 64% of the vote. 

Fact in focus: US House incumbents in Oklahoma have won 84 straight races dating back 34 years, including 4 repeat landside winners in 2008. 

Fact in focus: North Dakota Republicans have not won a US House or US Senate seat since 1982 despite dominating the state's presidential races.

Fact in focus: A majority of North Carolina's US House seats were won by "untouchable" repeat landside winners.

Fact in focus: Since 1998, Ohio incumbents have won 96 of 97 US House races. 

Fact in focus: New York Republicans won 31.6% of US House votes in 2008, but just three of 29 seats -- only 7% of Democratic voters failed to elect a candidate.