"I go against my party all the time," Donnelly said from the debate stage in Westville. "I've been with president 62 percent of the time. That's what we're supposed to do."
Unlike many Democratic campaigns across the U.S. that have been galvanized by Trump opposition, Donnelly touted his support for Trump's priorities.
That's not entirely a surprise. The vulnerable incumbent is one of a handful of Democrats running for re-election in states Trump won. But Donnelly has cast several high-profile votes against Trump and in line with Democrats, including his "no" vote this weekend on Trump's Supreme Court pick Brett Kavanaugh and the GOP led tax cut bill.
That gave Braun an opening to attack.
"He never sticks his neck out," Braun said. "He blows with the wind."
Donnelly entered the debate wanting to sow doubts about Braun's trustworthiness, while raising concern that, as a Republican, he would try to repeal the Affordable Care Act, which is sometimes referred to as "Obamacare."
Braun, on the other hand, hoped to focus on his own record as a "job creator" and political "outsider" while going after Donnelly for being a "career politician" who voted for the health care law.
But after years of Democrats running away from what had been a toxic issue at the polls, Donnelly boasted that he cast the "deciding vote" to save the health care law- the same wording the GOP formerly used in attack ads.
"I stand here proudly before you and all the people of Indiana to tell you I was the deciding vote that saved coverage for pre-existing conditions," Donnelly said, before attacking Braun for supporting a GOP-led lawsuit aimed at eliminating the law, including coverage for those with pre-existing conditions.
"Mike, I can hardly believe that you can stand here and tell everybody you are for coverage of pre-existing conditions," Donnelly said. "Stand here tonight and tell us you'll denounce that lawsuit."
While the two clashed, Donnelly showed an uncharacteristic willingness to go on the attack. Still, both largely stuck to well-rehearsed talking points that have been echoed throughout the campaign.
"It's going to be an awfully long evening if we just simply listen to them repeat their commercials back and forth to each other," joked Libertarian candidate Lucy Brenton, who was also at the debate.
While Braun argues he's a political outsider, that's not entirely true. He served on a school board near his hometown of Jasper and was elected to two terms in the Indiana House of Representatives - where he voted to hike the state's gas tax - before resigning to focus on his Senate campaign.
But after several terms in Congress and six years in the Senate, he said it was Donnelly's record that needs to be scrutinized.
"He never speaks up. Doesn't want to shake things up," Braun said. "You got be willing to buck your party boss, (Senate Minority Leader) Chuck Schumer, who tells the senator what to do on all the important legislation."
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