Many Democratic Party lawmakers reflexively bash President Trump every chance they get.

Not Sen. Joe Donnelly, D-Ind.

“I’ve voted with the president 62 percent of the time,” Donnelly told Fox News. “I’ve voted for a whole bunch of his nominees, voted for [Supreme Court Justice Neil] Gorsuch, we’ve worked together on the opioid issue. We’ve worked together on veterans issues.”

But Donnelly, one of the 10 Democratic senators trying to win re-election in a state Trump carried, voted no on the GOP’s tax reform package. And that vote may give the winner of next month’s Republican primary an Air Force One-sized boost.

“If Senator Donnelly doesn’t approve it,” President Trump told an Indiana crowd at an event promoting the tax package last September, “we will campaign against him like you wouldn’t believe.”

That kind of support has the potential to move the needle wherever the president pleases.

Trump beat Clinton by 19 points in 2016, with the state’s governor as his running mate, and benefitted from glowing endorsements by two of the state’s most legendary sports figures: Bobby Knight and Lou Holtz.

GOP party leaders believe they have a strong shot at flipping the Senate seat – but first they have to get though a bruising midterm primary that has two members of Congress angling for the chance to try and trounce Donnelly.

Rep. Todd Rokita, R-Ind., is doing this by donning a famous red-and-white “Make America Great Again” hat in a new television advertisement.

In another ad, Rokita’s campaign unearths past statements from Rep. Luke Messer, his opponent, where the candidate speaks critically about then candidate Trump.

Messer argues that Rokita’s recent vote against the Omnibus budget President Trump begrudgingly signed is proof that he’s not actually working to advance the administration’s agenda.

“My opponent, he talks Trump, Trump, Trump,” Messer told Fox News. “But when it’s time to show courage and vote for President Trump’s agenda, he votes no, no, no.”

But there’s not much difference between Messer and Rokita, according to a third candidate who is running as an outsider – businessman Mike Braun.

A slickly produced video on Braun’s campaign website shows the Senate hopeful quizzing constituents about Rokita and Braun, flanked by a cardboard cut-out of each.

One question Braun asks, about the Rokita and Messer cut-outs: “where do you think they live?” A woman responds: “Washington?” Braun answers “one of them does!”

Rep. Messer’s wife and kids live in Virginia, which has critics questioning where their Senator actually resides. Similar questions dogged longtime Republican Sen. Richard Lugar, who was upset in the 2012 GOP primary.

“I’ve got a home in Indiana that I’ve owned for 17 years,” Messer said. “My kid do need a full-time father, but I’ll tell you this – that’s not what Hoosiers are focused on.”

Indiana’s Republican primary, to determine who will square off against Donnelly, is May 8.

