There's a bit of worrisome news for Sens. Mitch McConnellAddison (Mitch) Mitchell McConnellSessions: 'We should be like Canada' in how we take in immigrants NSA spying program overcomes key Senate hurdle Overnight Finance: Lawmakers see shutdown odds rising | Trump calls for looser rules for bank loans | Consumer bureau moves to revise payday lending rule | Trump warns China on trade deficit MORE (R-Ky.) and John KerryJohn Forbes KerryFeehery: Oprah Dem presidential bid unlikely Dem hopefuls flock to Iowa Change in Iran will only come from its people — not the United States MORE (D-Mass.) in the latest SurveyUSA approval ratings of senators up for reelection this year.

As Senate Guru points out, McConnell and Kerry both have approval ratings below 50 percent, the benchmark for safe incumbents. McConnell's approval and disapproval ratings are even at 46 percent. Kerry's approval rating is at 49 percent, five points better than his disapproval rating.

Both men, however, will go into their races as favorites. McConnell's challenger is yet to be determined; former gubernatorial candidate Bruce Lunsford and businessman Greg Fischer are vying for the Democratic nod. McConnell has raised $12 million for his campaign, while neither Lunsford nor Fischer have raised much more than $1 million.

Kerry will face former House candidate Jim Ogonowski, who narrowly lost a House special election last year to Rep. Niki Tsongas (D-Mass.). The former Democratic presidential nominee has received about $9.4 million in contributions, nearly 10 times the amount than Ogonowski has.

Both McConnell and Kerry are also poised to benefit from running in a presidential year, when Kentucky voters tend to vote Republican and Massachusetts voters lean heavily toward Democrats.