Sen. Joe Donnelly, one of a handful of vulnerable Senate Democrats from Trump-won states up for re-election this cycle, held a slight 3-point lead over his GOP opponent in a new poll.

Donnelly paced businessman and political newcomer Mike Braun, the Republican nominee backed by President Donald Trump, 44 percent to 41 percent among likely voters, according to an NBC News/Marist poll released Wednesday.

But Braun’s deficit was well within the survey’s margin of error for the 576 likely voters interviewed by phone from Aug. 26 through Aug. 29.

Lucy Brenton, a Libertarian, received support from 8 percent of the likely voters polled.

Donnelly led by a 6-point margin, 49 percent to 43 percent in a head-to-head match-up with Braun. And among registered voters, he edged Braun, 48 percent to 42 percent.

Republicans have targeted the first-term senator as they seek to widen their 51-49 majority over the Democrats in the chamber. 

Donnelly will need to remain in the good graces of the political independents in the state if he wants to win a second term, and, according to the poll, he appears to be doing a good job so far.

Among independent likely voters, the senator led Braun by 20 points, 45 percent to 25 percent.

Donnelly, like the 10 other Senate Democrats seeking re-election in states Trump won in 2016, has sought crossover appeal by voting to confirm some of Trump’s federal government appointees, approving the appropriations package that included border wall funding earlier this year, and quashing a Republican effort to dismantle the Affordable Care Act, parts of which are widely popular in many of the states Republicans are targeting this November.

Trump won Indiana, the home state of his vice president, former Gov. Mike Pence, by 20 points in 2016.

Inside Elections with Nathan L. Gonzales rates the race a Tossup.

Overall, the pollsters interviewed 955 Indiana adults. The overall error margin for the entire sample is +/- 3.9 percent.

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