Alabama Rep. Martha Roby is heading to a primary runoff against party-switching former Rep. Bobby Bright after failing to garner a majority of Republican votes Tuesday night.

Roby and Bright led a five-candidate field with 39 percent and 28 percent respectively. The primary runoff will take place on July 17.

The challenge to the 2nd District congresswoman stems largely from her criticism of candidate Donald Trump during the 2016 campaign. Roby said at the time she would not vote for Trump after a tape surfaced of him bragging about grabbing women by the genitals. He went on to carry the district by 32 points.

Roby, who is in her fourth term, was added to the National Republican Congressional Committee’s new Primary Patriot program, which helps incumbents facing primary challengers. The U.S. Chamber of Commerce also spent $250,000 on television ads on her behalf ahead of Tuesday’s primary, according to Federal Election Commission documents.

Bright previously represented the district for a term as a Democrat before losing to Roby by 2 points in 2010. He also previously served as the mayor of Montgomery.

In Congress, Bright was a conservative Democrat, voting against President Barack Obama’s signature health care law. But his vote for House Minority Leader Nancy Pelosi as speaker dogged him in his re-election race and will likely be an issue again in the runoff against Roby.

“Martha Roby is strongly supported by her district because she fights for her constituents and has their best interests in mind,” NRCC spokeswoman Maddie Anderson said in a statement last week. “Her primary opponent clearly does not share the same sentiment, given that he voted for Nancy Pelosi for Speaker.

Bright switched parties to run against Roby, telling reporters in Alabama that the GOP reflected his conservative values. He also pointed out that other big-name Republicans including Trump, Alabama Gov. Kay Ivey, and Alabama’s senior senator Richard C. Shelby were also former Democrats.

The other GOP hopefuls in the primary included state Rep. Barry Moore; Iraq War veteran Tommy Amason; and Rich Hobson, a longtime aide to Roy Moore, who lost the special election for an Alabama Senate seat in December amid allegations of sexual misconduct.

The 2nd District includes most of Montgomery County and rural portions of the southeastern corner of the state. The winner of the runoff will face Democratic business analyst Tabitha Isner in November after she easily won Tuesday’s party primary. Inside Elections with Nathan L. Gonzales rates the race Solid Republican.Watch: Which House Races Are the Parties Targeting? Look to the Money, the TV Ad Money