(Reuters) - President Donald Trump will travel to Minnesota on Thursday for his first campaign rally since Democrats in Washington launched an impeachment inquiry against him, his latest event in one of the states he lost in 2016 but believes he can pick up next year.

U.S. President Donald Trump speaks as he awards the Presidential Medal of Freedom to former Attorney General Edwin Meese at the White House in Washington, U.S., October 8, 2019. REUTERS/Leah Millis

Trump’s path to re-election in November 2020 depends on clinching a cluster of farm and Rust Belt states decided by slim margins in 2016. Minnesota, which Trump lost by 1.5 percentage points to Democrat Hillary Clinton, is a key target, his campaign said.

He faces tough odds. No Republican presidential candidate has won Minnesota since Richard Nixon in 1972. Trump’s unfavorability number in Minnesota is 11 points higher than his favorability rating, according to Morning Consult polling.

But Trump has said it was a mistake not to spend more time and money in the Midwestern state in 2016, and his campaign vowed the mistake would not be repeated.

“This is a campaign on offense. This is a campaign going into states other campaigns couldn’t put in play,” Bill Stepien, a senior Trump campaign adviser, said in a phone interview.

Trump will again use his rally to fire up his base, which has remained firmly behind him in opinion polls after Democrats last month launched an impeachment investigation into the president.

The House of Representatives probe centers on a whistleblower’s allegations that Trump used U.S. military aid to secure a promise from Ukraine’s president to investigate former Vice President Joe Biden, a leading candidate for the Democratic presidential nomination, and his son Hunter, who was on the board of a Ukrainian energy firm.

Trump has denied wrongdoing. The White House said on Tuesday it would refuse to participate in the “partisan and unconstitutional” impeachment inquiry.

The rally is taking place in Minneapolis in the congressional district of Representative Ilhan Omar, a progressive Democrat who is one of Trump’s most vocal critics.

The Somalia-born congresswoman was one of four female lawmakers who Trump said this summer should “go back” to where they came from if they did not like his policies. At a rally in North Carolina soon afterward, Trump supporters chanted: “Send her back” when he again blasted Omar.

Ahead of Trump’s visit to her state this week, Omar and other Democratic officials said the president’s rhetoric was not in line with their local values.

“Minnesota stands for peace, equity, and justice - everything you are against,” Omar tweeted on Tuesday.

RUNNING UP THE RURAL VOTE

Trump’s campaign disagrees.

Like Pennsylvania, which Trump won in 2016, Minnesota has a large rural population that can erase Democratic gains in urban centers.

The campaign points to the state’s 8th Congressional District, home to Minnesota’s mining industry and once a reliable Democratic stronghold, as a sign that Trump’s message resonates with voters there.

Trump won the district by 15 percentage points in 2016, after Democratic President Barack Obama won it four years earlier by about 5 points.

“It’s the epicenter of Minnesota’s changing political culture,” Stepien said. “That’s a district that sees what’s happening in D.C., with Democrats lurching further and further to the left. It’s a district that wants jobs, wants mining, wants less regulation, all the things that Trump talked about in 2016.”

Trump lost the twin cities of Minneapolis and St. Paul by greater margins than Republican presidential nominee Mitt Romney in 2012. But he won the rest of the state by bigger numbers than Romney.

Republican strategists in the state said the suburban counties around Minneapolis would decide the election. Polls show Trump struggling nationally with suburban voters.

“I understand why the campaign needs to show it’s expanding the map, but I think winning Minnesota is going to be a real challenge,” said one Republican strategist, who requested anonymity to speak candidly.

Ken Martin, chair of Minnesota’s Democratic Party, said the Trump campaign had built the biggest political operation he had ever seen for any Republican this early in the election cycle, but that it would not translate to victory. He said Trump was unpopular in the fastest-growing parts of the state - the suburbs and exurbs.

“If Trump think he’s going to flip Minnesota just by dealing with folks in greater Minnesota, which is the rural parts of the state, he’s obviously not a math wizard,” Martin said. “He needs to understand where the votes come from in the state, and where those votes come from, he’s not very popular.”

The planned rally has fanned local partisan flames.

Minneapolis Mayor Jacob Frey, a Democrat, drew scrutiny for initially suggesting the president was not welcome in the city.

In an emailed statement, Frey said the president had targeted the most marginalized members of the city’s community with his divisive language, which is amplified at his rallies.

“So while our thriving city is open to everyone, I will continue to stand alongside people in Minneapolis and reject speech and behavior that make any of our residents less safe,” Frey said.

The head of the Minneapolis police union, Bob Kroll, said many officers wanted to go to Thursday’s rally wearing their uniforms to show support for the president but were banned from doing so by the police department.

In response, the police union has been selling “Cops for Trump” T-shirts for officers to wear instead.