Joe Donnelly J. Scott Applewhite/AP In what is gearing up to be an eventful and contentious Senate race in Indiana, a mariachi band has been added to the mix.

During a recent campaign stop, the National Republican Senatorial Committee sent a full Mexican mariachi band to meet Democratic Sen. Joe Donnelly.

The stunt was an attempt to call attention to what the GOP sees as Donnelly's hypocritical record on outsourcing and trade.

While the freshman senator has been an outspoken critic of international trade agreements that encourage outsourcing, including the North American Free Trade Agreement, the Associated Press revealed last month that, for at least a year, Donnelly's family business has used Mexican factories to produce dye for its ink pads.

Donnelly's brother owns the company, Stewart Superior Corp., and the senator served as a corporate officer and the company's general counsel prior to his election to Congress in 2006, and has reportedly invested up to $50,000 in the company.

Following the revelation, Donnelly, whom the GOP has dubbed "Mexico Joe," reportedly sold his stock in the business.

Republicans have jumped on the opportunity to attack Donnelly, who is widely seen as one of the most vulnerable Senate Democrats up for reelection in 2018, given that President Donald Trump swept Indiana by 19 points in November.

"Joe Donnelly can try to make Hoosiers forget about his family business's outsourcing controversy," an NRSC spokesman said in a press release, "but we'll make sure it's the first thing on voters' minds when they head to the polls in 2018."

Donnelly called the accusation a distraction from his stance on outsourcing and minimized his involvement in the company.

"Some folks in Washington want to make the stock I've owned in my brother's company into a distraction from our work to end outsourcing," the senator said in a statement. "I won't let them distract us, so I'm selling the stock in my brother's company — a company I haven't had an active role in for 20 years."

The GOP primary race, which is just getting underway, is promising to see a contentious battle between two congressmen, and former college classmates, Todd Rokita and Luke Messer.

Watch the video of the mariachi band below: