Great Falls, Montana (CNN) As President Donald Trump heads to Montana in an effort to torpedo the re-election campaign of Sen. Jon Tester, the Montana Democrat placed a full-page ad in 14 of the state's newspapers touting the 16 bills he supported that the President has signed.

The play by Tester's campaign underscored the difficult re-election campaign facing Tester in this deeply red state where Trump beat Hillary Clinton by 20 points in 2016.

Tester, who is the top Democrat on the Senate Veteran Affairs' Committee, infuriated Trump with his fervent criticism of Ronny Jackson, who was briefly Trump's nominee to be secretary of veterans affairs -- making Tester a top target for Trump's trolling on Twitter.

Though Jackson ultimately withdrew from consideration as a result of allegations of misconduct and poor administration of the White House medical office , the President called for Tester to resign, claiming that Tester made false claims against Jackson, who was the President's personal physician.

"The great people of Montana will not stand for this kind of slander when talking of a great human being," Trump tweeted in April

In an interview with Fox News after Jackson withdrew, Trump said Tester would have a "big price to pay in Montana" over the accusations.

The President is following through on that threat with his visit to Montana Thursday where he will rally his voters in support of Republican state auditor Matt Rosendale, who won a June primary with 33% of the vote for the nomination to face Tester

In the newspaper and radio ad, Tester's campaign points out that the Montana Democrat has voted with the President on issues like accountability for the Veterans Administration.

The ad says "Welcome to Montana & Thank you President Trump," noting that Trump signed Tester-supported bills addressing issues from care for veterans to response times of first responders.

Republicans currently hold a 51 seats in the 100-member Senate. As Democrats seek to win control, the retirement of Supreme Court Justice Anthony Kennedy has intensified the heat on Tester and other red state Democrats, who will face intense pressure to support the President's Supreme Court nominee.

Tester, who was born in Montana and still farms wheat and lentils on the land that his grandparents homesteaded near the town of Big Sandy, does not face a particularly strong Republican challenger in Rosendale.

On his campaign website, Rosendale describes himself as a rancher and businessman, but Democrats have excoriated him for that claim, noting that he moved to Montana in June 2002 from Maryland, where he focused on real estate development.

Both his Democratic and Republican opponents have poked fun at his Maryland accent. In 2011 while serving in the Montana legislature, Rosendale told a Maryland publication, MyEasternShoreMD , that he leases his land to farmers and to a cattle rancher.

"There's a bunch of irrigated ground and I lease it to one of my neighbors and he grows crops on it, and then there's dry farmland and I lease that to another neighbor, and then I've got all the native pasture and I lease that to another guy who runs cattle," he told MyEasternShoreMD.com.

Rosendale added that he fixes fences on his property, rides his horse to "check things out" and then allows 50 to 70 people to come on his property to hunt.

Some negative campaign ads have mocked Rosendale as "Maryland Matt."

In a Wall Street Journal interview this week , Tester said he would not watch Trump's rally and -- after holding a roundtable discussion on trade -- would likely be on his tractor.

"I doubt Rosendale could change the oil on a tractor," Tester told the Journal.

But Trump has shown an unique ability to elevate even obscure contenders by rallying supporters and turning out his base. He will likely point to Tester's opposition to the tax bill, as well as Supreme Court Justice Neil Gorsuch, as votes that were out of step with Montanans.

In the 2012 race, Tester beat then-Rep. Denny Rehberg 49% to 45%.