Voters in the 50-64 age group have been an accurate barometer in presidential elections, voting narrowly for Clinton in 1992 and by a larger margin in 1996, slightly favoring George W. Bush in 2000 and 2004 and giving a one-point edge to Barack Obama in 2008.

4. Turnout. One given: the 50-plus bloc will vote in November at a higher rate than their younger counterparts. For those who started voting in the 1950s and 1960s, voting is practically a reflex. These people "were taught in their homes and high school civics classes that voting was a fundamental responsibility of citizenship, and they felt guilty if they did not fulfill this responsibility," Emory University professor Alan Abramowitz wrote in his recently published book, The Disappearing Center: Engaged Citizens, Polarization, and American Democracy.

According to a Census Bureau report released in May, 64 percent of the nation's voting age population participated in the 2008 presidential election. But the generation gap was wide –– just 49 percent of those 18 to 24 voted, compared with 72 percent of those 55 to 74. In a poll released July 1, the Pew Research Center found nearly 80 percent of those 50-plus saying they were "absolutely certain" to vote in November, compared with 50 percent of those in the 18 to 29 age group.

In that poll, 57 percent of the youngest voters said they would support the Democrat in their congressional district. Among 50-plus voters, 52 percent said they would vote for a Republican in their district. Even among 50-plus women, almost half said they'll vote Republican this time around, although a plurality of all women called themselves Democrats in presidential election polls going back to 1972.

Outlook. Of course, nobody knows for sure when the electorate's frame of mind might change. Freedman questions whether the anti-incumbent mood will survive the summer, citing "a difference between saying you'd vote for someone with absolutely no political experience and actually voting" that way.

But not all challengers will be political newcomers, leaving Democrats on the defensive because they have more seats at stake. Barring a big drop in the unemployment rate or a sudden surge in the economy, Baker, like many political experts, projects the House will revert to Republican control.

That's fine with Rountree, but his main goal transcends party.

"We want to make sure that the people we put on the ballot are true conservatives," he says. "I don't think a lot of us care which party it is. We just want to see good quality people in there."

David Morris is former executive editor of CongressDaily, a twice-a-day report about Capitol Hill.