A new Gallup poll shows that congressional incumbents should worry about re-election - at least a little bit.

More than 70% in the poll say that incumbents don't deserve re-election while only 22% say they do. This represents the lowest percentage of voters who believe incumbents should be returned to Washington in more than 20 years.

Politico:

According to the Gallup survey, only 22 percent of registered voters believe that most members of Congress deserve reelection and 72 percent believe they don’t. If the results hold in November, the “deserve re-election” figure will be the lowest mark since Gallup began tracking the question in 1992.

In particular, only 16 percent of independent voters say most lawmakers deserve to be reelected. This mark is compared with 28 percent of Democrats and 22 percent of Republicans.

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Still, 50 percent of registered voters say their personal member of Congress deserves to be reelected.

Congress has a 15 percent approval rating, according to the latest Gallup congressional approval rating survey conducted May 8-11. It has an 80 percent disapproval rating.

Gallup has calculated that there is a correlation between the level of voters who think that most lawmakers deserve reelection and congressional turnover rates during election years. If the low percentage mark holds in November, the report says, incumbents might perform worse this November compared to previous years.

This attitude will probably not result in a wholesale turnover in Congress. The 2010 redistricting by both parties assures re-election for 95% of members - normally. But there may be a few more open seats that change party hands as a result of the anti-incumbent mood. And some Democratic incumbents may not be able to overcome their support for Obamacare, although most are shielded from the fallout by running in districts that are considered "safe."

The exception would be in a tidal wave election where even those Democrats who won 55% of the vote in 2012 might be tossed out. That happened in 2010 and may happen again if certain dominoes fall the GOP's way.

The current thinking among experts is that Republicans may pick up a few House seats - "single digits"  or "5-8 seats" depending on the analyst. This assumes a mild wave. But if it becomes a tsunami, all bets are off and that number of pickups could easily double.