At least seven Senate incumbents struggling below halfway mark in polls

At least seven Senate incumbents in competitive races are struggling to reach the 50 percent mark in the polls.

The group includes both Democrats and Republicans — showing incumbents in both parties are subject to voters’ wrath.

An analysis by The Hill of 10 competitive Senate seats with incumbents seeking re-election finds only Sens. Kirsten GillibrandKirsten GillibrandThe Trail 2016: The newrevolution begins Democratic National Convention event calendar Texas rep uses Snapchat to prompt border control discussions MORE (D-N.Y.), Ron WydenRon WydenDems push for US, EU cooperation on China's market status Senate Dems push Obama for more Iran transparency Watchdog faults Energy Department over whistleblower retaliation MORE (D-Ore.) and Charles GrassleyChuck GrassleyTop Dem Senate hopefuls to skip convention Election to shape Supreme Court Why one senator sees Gingrich as Trump's best VP choice MORE (R-Iowa) safely above 50 percent in the most recent polls.

Sens. David VitterDavid VitterDavid Duke will bank on racial tensions in Louisiana Senate bid Former KKK leader David Duke running for Senate Six senators call on housing regulator to let Congress finish housing finance reform MORE (R-La.) and Patty MurrayPatty MurrayOur children, our future – bridging the partisan divide Overnight Energy: Officials close in on new global emissions deal NBA pulls All-Star Game from NC over bathroom law MORE (D-Wash.) are on the cusp, with recent polls showing them at or below 50 percent.

The endangered senators include Barbara BoxerBarbara BoxerDem suggests race factored into Obama Senate endorsement Obama, Biden back Kamala Harris in Calif. Senate race Tim Scott says he was targeted by Capitol Police MORE (D-Calif.) and Michael BennetMichael BennetBacteria found ahead of Olympics underscores need for congressional action for new antibiotics Top GOP senator: Trump will have little effect on Senate races Black GOP Senate candidate rips Obama MORE (D-Colo.), each of whom only reached 49 percent in recent polls, as well as Majority Leader Harry ReidHarry ReidDems put immigration front-and-center on convention's first day Dem ad blasts Indiana senate candidate on Social Security Super-PAC targets Portman on trade MORE (D-Nev.), who only reached 48 percent in the past two months of polls. Russ Feingold (D-Wis.) can’t crack 46 percent, while Blanche Lincoln (D-Ark.) appears to be in the worst shape. Lincoln’s highest polling number all summer was 35 percent in a mid-July Reuters/Ipsos survey.

Labor Day marks the start of the final stretch of the campaign season. Any incumbent polling below 50 percent at that point is considered in serious trouble.

But Ross Baker, a political scientist at Rutgers University, said the incumbents still have time to recover strength.

“Obviously, below 50 percent is a firebell in the night for any incumbent — but it’s not Labor Day yet,” Baker said. “Looking at it race by race, even though there a large number of them, some of those sub-50s will recover nicely.”

Tom Jensen, director of Public Policy Polling (PPP), which conducts a wide variety of national and state-specific congressional polls, says the high number of endangered incumbents might be the most he’s ever seen.

“There’s definitely a high number, and almost an unprecedented level of discontent with politicians,” Jensen said. “It seems the economic recession has created a recession in political approval ratings. Very few people have been unable to buck that trend.”

Specifically, Jensen said PPP has conducted polls on about 80 Senate and gubernatorial races this year, with fewer than 10 percent of candidates receiving ratings above 50 percent.

“What we're also finding right now is that independent voters are down on everyone,” Jensen said. “Almost no senator has positives with them. Senators are also running into resistance in their own party. People from the opposing party dislike them more strongly, but often their own bases are not as happy with them either.”

The low ratings do not necessarily translate into trouble. Vitter’s numbers are still high enough to hold a double-digit lead over Democrat Charlie Melancon. Boxer, Reid, Murray and Feingold hold single-point leads.

Both Baker and Jensen said the candidates who are faring the best are those who attack early and paint their opponents as a worse alternative. That strategy helped Sen. John McCainJohn McCainSyria activists cheer Kaine pick Clinton brings in the heavy hitters Guess which Cuban-American 2016 candidate best set themselves up for 2020? MORE (R-Ariz.) define former Rep. J.D. Hayworth (R-Ariz.) as unsuitable for office, Baker noted, while Sen. Lisa Murkowski (R-Alaska) suffered her likely primary loss because she was complacent about Republican primary rival Joe Miller.

“Being below 50 percent does signify danger, but not necessarily a calamity,” Baker said. “The more experienced and savvy incumbents have developed a way of fending off attacks.

“Reid is a good example. He was ready to go with defining and framing ads to portray [GOP challenger Sharron] Angle as far out of the mainstream, and she’s basically spent the whole campaign disavowing things she’s said in the past, on the record.

“So this is much stronger of an anti-incumbent mood than usual for a mid-term election, both in the severity and the duration. There will be a lot of casualties. But it’s also a test of incumbents.”

Jensen said it is likely too late for any of the sub-50 percent incumbents to crack that threshold. Yet he agreed with Baker that it might be enough to simply make their opponents seem like a worse choice.

“Clearly, Reid has had some success with that in Nevada,” Jensen said. “I don’t think any of them are going to be liked any more, but it’s about the lesser of two evils. If the 2008 election was about hope, 2010 seems to be about making people hate your opponent more than they hate you.”