GOP poll: Ernst leads in key Senate race
© Ernst for U.S. Senate

Iowa state Sen. Joni ErnstJoni Kay ErnstSenators push mandatory sexual harassment training for members, staff We must do more to celebrate women small business owners EPA walks back biofuels mandate changes MORE (R) has a lead over Rep. Bruce BraleyBruce BraleyOPINION | Tax reform, not Trump-McConnell feuds, will make 2018 a win for GOP Ten years later, House Dems reunite and look forward Trump: Ernst wanted 'more seasoning' before entertaining VP offer MORE (D-Iowa) as they begin their general election battle, according to a new survey conducted by GOP pollster Vox Populi.

Ernst leads Braley by 49 percent to 44 percent, a flip from pre-primary polling that had found Braley in the lead.

Her big primary win seems to have given Ernst a bump in the race, as did heavy spending by outside groups on her behalf. Her three primary opponents never hit hard against Ernst in the primary.

The race is one of a handful of battles that will determine Senate control. If Ernst can maintain her newfound lead, the GOP's chances of winning back the Senate increase greatly.

Partisan polls should always be taken with a grain of salt. But this poll is in line with the first nonpartisan public poll of the race, one conducted by Loras College that found her leading by 48 percent to 42 percent.

The automated poll of 667 active voters was conducted from June 4-5, the first days after the primary, and has a margin of error of plus or minus 3.8 percentage points.