(Photo credit: AP Photo/Susan Walsh)

(Photo credit: AP Photo/Susan Walsh)

Rep. Henry Waxman (D-Calif.) announced Thursday that he won't seek reelection to Congress this November.

The lesson? Democrats aren't really counting on re-taking the House in 2014.

Waxman is the fourth top Democrat on a House committee who has either called it quits or opted to run for another office, and a fifth -- House Agriculture Committee Ranking Member Collin Peterson (D-Minn.) -- said this week that he's still weighing his options.

In other words, about 20 percent of the people who stand to become chairmen if Democrats re-take the House are choosing not to stick around (there are 20 standing committees in the House) -- and possibly 25 percent, if Peterson calls it quits.

"The House Democrats don't think they're going to be wielding the gavels," National Republican Congressional Committee Chairman Greg Walden (R-Ore.) told my colleague Paul Kane shortly after Waxman's retirement was announced.

The others headed out the door are Rep. George Miller (D-Calif.) -- a classmate of Waxman's in the post-Watergate election of 1974 who announced his retirement earlier this month -- and Mike Michaud (D-Maine) and Ed Markey (D-Mass.). Michaud is running for governor, while Markey won a special election for Senate in June.

In the latter two cases, leaving the House might have had as much or more to do with the fact that they had very winnable races for higher office sitting right in front of them. It's really Miller, Waxman and (potentially) Peterson who tell the story. All three would likely head up major House committees in a Democratic-led 114th Congress -- Miller on Education, Waxman on Energy and Commerce and Peterson on Agriculture.

Of course, age and electoral prospects play a role. Waxman and Miller are among the 11 longest-serving members of Congress, Waxman had his first tough race in decades in 2012, and Peterson is an emerging GOP target in a district that Mitt Romney won by 10 points in 2012. But all three were very likely to return to Congress if they ran again.

The fact that they aren't sticking around suggests the cost-benefit analysis of serving another two years versus their odds of becoming chairmen isn't looking great.

That's not to say Democrats have bigger retirement problems than the GOP (Republicans are clearly hurting more right now), or that it's impossible for Democrats to win back the House -- just that they these longtime members don't think it's worth sticking around to find out.

Updated at 11:21 a.m.