2. Rightward tilt. The anger among 50-plus Americans, 40 percent of the adult population, is "a revolt of the haves and those who want to protect what they have," Baker says. In 2007, American families headed by someone 50-plus held 75 percent of the nation's personal net worth, according to AARP's Public Policy Institute.

"There's almost kind of an intellectual compass that points in a more conservative direction as people age," Baker says. "The older you get, the more you have to conserve."

Rountree moved away from the Democratic Party after Jimmy Carter was elected president in 1976, noting that, then a military recruiter, he watched as Carter's policies "decimated the ranks." He moved deeper into the conservative Republican camp after starting his own business.

Rountree wasn't alone, according to exit polls tracking today's youngest 50-plus voters over key elections.

In 1980, when Rountree and his cohorts were in the 18 to 29 age range, 44 percent of younger voters called themselves Democrats and just 27 percent called themselves Republicans.

In 1992, when most of them were in the 30 to 44 age group, 41 percent said they were Democrats and 38 percent labeled themselves Republicans.

In 2006, though Democrats took control of Congress, the gap for those voters –– by then in the 45 to 59 age group –– tightened to 37 percent saying they were Democrats and 35 percent saying they were Republicans.

3. Experience. Many retirement-age voters have been down the path of dissatisfaction before. In a July 1992 study of potential voters, the Times Mirror Center for the People & the Press (now the Pew Research Center) found most 50-plus Americans calling for new leaders, "even if they are not as effective as experienced politicians."

That fall, Arkansas Gov. Bill Clinton defeated President George H.W. Bush, and two years later, Democrats were voted out of power in Congress. Today, the youngest of those 50-plus voters from 1992 are 68 years old.

Those voters have been through the health care debate before –– after Clinton was elected to his first term –– and have lived through earlier stock market plunges and recessions, so an inclination to try new candidates can be seen as a tacit acknowledgment that politics as usual hasn't worked.