Republican candidates backed by US President Donald Trump are clinging to narrow leads in elections in Ohio and Kansas, offering encouraging signs for opposition Democrats heading into November's midterms.
Republicans looked likely to hold on to a House of Representatives seat in a reliably conservative district in Ohio, where Troy Balderson led Democrat Danny O'Connor by about 1700 votes in a special election.
The final result could be days away as state officials count more than 8,000 provisional and absentee ballots.
In Kansas, staunch Trump ally Kris Kobach held a lead of fewer than 200 votes over current Governor Jeff Colyer, in a primary race that could take days or weeks before a final result is determined.
Democrats performed dramatically better than expected in the last federal special election before the midterms, when Republicans are defending majorities in both the House and Senate.
"This gives me optimism," Democratic National Committee chairman Tom Perez told CNN on Wednesday.
Trump, on Twitter, took credit for Balderson's lead, claiming his fellow Republican's campaign took "a big turn for the better" after he campaigned for him in the district on Saturday.
Democrats need to win 23 more seats in the House and two in the Senate to control congress and put the brakes on Trump's agenda.
All 435 House seats, 35 of 100 Senate seats and 36 of 50 governors' offices are up for grabs in November.
Three other states held nominating contests on Tuesday, including a battle for governor in Michigan in which mainstream Democratic candidate Gretchen Whitmer beat progressive Abdul El-Sayed.
Whitmer received more than half of the vote as Democrats angle to take back the governor's office in the Midwestern state.
And Laura Kelly's Democratic primary win in Kansas means 11 women will contest governorships in November - one more than the previous 1994 record.
At least 173 female major party nominees will run for the House, beating the record of 167 from 2016.
Former Michigan state lawmaker Rashida Tlaib won the Democratic nomination to run unopposed for a House seat, setting her up to become the first Muslim woman elected to congress.
And Sharice Davids has became the state's first Native American and gay nominee for congress.
The 38-year-old attorney and activist prevailed in a close six-candidate Democratic primary and will face four-term Republican Representative Kevin Yoder.
Democrats are targeting Yoder because Democrat Hillary Clinton narrowly won the district in the 2016 presidential race.
