Jon Ossoff, a 30-year-old political novice, is leading a field of 18 candidates for a U.S. House of Representatives seat that was vacated when Trump named Tom Price as his health secretary.
An Ossoff win would not tip the balance of power in Washington but could weaken the already shaky hold Trump has on his fellow Republicans by encouraging lawmakers to distance themselves from him.
Georgia's 6th District has elected Republicans to the House since the late 1970s, but Trump only carried it by 1 percentage point in the November presidential election.
Ossoff hopes to win an outright majority in Tuesday's vote, a "jungle primary" with all 18 candidates from both parties on the same ballot. If no one reaches 50 percent, the top two vote-getters square off on June 20.
Republicans say they could beat Ossoff in a one-on-one contest. The party avoided embarrassment last week when it narrowly held a conservative Kansas seat vacated when Trump tapped Republican Representative Mike Pompeo to head the Central Intelligence Agency. [nL3N1HI57X]
With the slogan "Make Trump Furious," Ossoff aims to galvanize opposition to a president struggling with an approval rating that has not topped 50 percent since he took office on Jan. 20, according to Reuters/Ipsos polling.
"We have an amazing chance here, an extraordinary moment for Georgia," Ossoff told volunteers as they headed out for a round of door-knocking on Monday afternoon.
Republicans in the race are split among Trump supporters and candidates trying to hold the president at arm's length.
Despite controlling the White House and both chambers of Congress, Republicans have yet to enact major legislation to fulfill campaign promises.
Trump blasted Ossoff on Twitter and said in a robocall that the Democrat would "raise your taxes, destroy your healthcare, and flood our country with illegal immigrants."
Ossoff said on CNN that Trump was misinformed about his positions and that he was focused on issues affecting the northern Atlanta suburbs, not Washington.
Ossoff has drawn volunteers and donors from out of state who see the race as a way to strike a blow against Trump.
"We need to see a balance in our country, a check on President Trump," said Vicki Hardin Woods, a retiree who traveled from Salem Oregon, to volunteer for the campaign. "This is one the first opportunities to make that happen, and I wanted to be a part of it."
Ossoff raised a stunning $8.3 million in the first quarter, forcing Republicans to spend heavily against him.
Banner and thumbnail credit: Reuters