Former Indiana Sen. Evan Bayh leads Rep. Todd Young 54 to 36 percent in the poll.
The two GOP senators supported a 2013 gun-control proposal.
Rep. Patrick Murphy's dad gave a $1 million donation to a group backing his campaign.
Hassan dodged repeated questions about Clinton's untrustworthiness in an interview.
Russ Feingold's campaign is accusing a woman of trying to infiltrate its offices.
The super-PAC knocks Sen. Kelly Ayotte for supporting Donald Trump.
It's the second time since leaving office he has been listed as inactive in the state.
The Senate Leadership Fund is spending $10.5M on television with the rest for radio and mail.
The environmental activist praised Patty Judge as an "environmental champion."
Sen. Chuck Grassley is leading his primary challenger by 9 points in Iowa.