FAYETTEVILLE, N.C./WASHINGTON - US President Donald Trump is going all-out to try to keep a North Carolina district in the Republican column in a special congressional election on Tuesday that may serve as a bellwether for his own fortunes in 2020.

Trump went to Fayetteville, a city in North Carolina's 9th Congressional District, on Monday to rally Republican supporters in a repeat election of a 2018 contest that was tainted by fraud. Both Republicans and Democrats expect Tuesday's election to be close and to provide clues about what might happen in presidential and congressional elections next year.

Republican Dan Bishop, a 55-year-old state senator who has embraced Trump's policies and some of his political tactics, is facing 36-year-old Democrat Dan McCready, a small-businessman and U.S. Marine Corps veteran, in Tuesday's race.

Bishop's campaign ads have said McCready "admires socialism" and linked him to the "Squad," a group of progressive House Democrats that Trump has repeatedly attacked.

Trump picked up on the theme, one of his favorites against Democrats running in 2020.

"To stop the far left, you must vote in tomorrow’s special election," Trump told the cheering crowd. "Tomorrow is your chance to send a message to the America-hating left."

Bishop's campaign says the most important issues are taxes, the economy and immigration, while McCready has focused his race on healthcare, education and the pay of North Carolina teachers.

"I share your values. I'm not ashamed of your values. I'm going to defend your values in Washington, D.C.," Bishop said at the rally, calling Trump a "great fighter" against "socialist" Democrats.

McCready met with fellow veterans in Fayetteville hours before Trump's speech and talked about how Americans were getting "crushed" by healthcare costs. He sent out a fundraising email after the Republican rally, headlined: "Trump just attacked me on stage."

Opinion polling indicates a tight race, with turnout an important factor. The result will not affect the balance of power in the Democratic-controlled House of Representatives.

U.S. Vice President Mike Pence also campaigned for Bishop, and addressed the evening rally before Trump.

Trump said he believed Bishop had a good chance of winning and that the contest had become "less close" since his own involvement began about two weeks ago. Trump stressed, however, that "I'm not running."

Trump has called North Carolina's Republican Party chairman several times for updates on the campaign, a Republican involved in the special election said.

The sprawling 9th District, a combination of suburban and rural areas stretching south and east of the city of Charlotte, has been represented by Republicans for decades, and voted for Trump by about 12 percentage points in 2016. A Republican loss would be a worrisome sign for the president and his party.

But Democrats are daring to hope for an upset that would build on their takeover of the House from Republicans in elections last year and make further inroads in "Trump country." -Reuters