Aug 8 (Reuters) - A hotly contested race in Ohio for a U.S. House of Representatives seat that has gone Republican for more than 30 years remained too close to call on Wednesday, in an encouraging sign for Democrats heading into the Nov. 6 elections.
Republican Troy Balderson led Democrat Danny O'Connor by about 1,700 votes with all precincts reporting, but the final result is likely to be days away as state officials count more than 8,000 provisional and absentee ballots.
Even if Balderson is eventually declared the winner, the narrow margin is little comfort for Republicans as they head into the November vote. It is certain to hearten Democrats, who performed dramatically better than expected.
The close Ohio special election has become a referendum on Republican President Donald Trump's leadership and a last chance to gauge Democratic strength ahead of November's midterm elections, in which the Republicans are defending majorities in both the House of Representatives and the Senate.
"This gives me optimism," Democratic National Committee Chairman Tom Perez told CNN on Wednesday.
Four other states held nominating contests, including a battle for governor in Michigan in which a mainstream Democratic candidate beat a progressive and a high-profile conservative challenge to the incumbent Republican governor in Kansas that was also still too close to call on Wednesday.
The races highlighted the challenges both parties face heading into November, with Democrats facing the limits of their more liberal wing in the U.S. Midwest and national Republicans split under Trump, whose voice still appeared to drive his base to his preferred, more firebrand choices that fellow conservatives worry could lose in the general election.
The Democratic race for governor in Michigan tested the electoral power of the party's progressive wing. However, former Detroit health director Abdul El-Sayed lost his bid to become the country's first Muslim governor to a more moderate Democrat, former state Senate leader Gretchen Whitmer.
In Kansas, conservative firebrand and staunch Trump ally Kris Kobach clung to a lead of less than 200 votes in the Republican gubernatorial primary over current Governor Jeff Colyer with most votes counted. Both men had about 41 percent of the vote in Kansas. Kobach has faced criticism for his hard-line views on immigration and efforts to remove voters from the rolls that he said is necessary to fight voter fraud.
Ohio's contest drew an avalanche of national attention in recent weeks as opinion polls showed it tightening, with Republicans and their allies outspending Democratic groups by more than 4 to 1.
Trump took credit for the Republican's lead, saying on Twitter that Balderson's campaign took "a big turn for the better" after he campaigned for him in the district on Saturday.
Other Republicans, including Vice President Mike Pence and Ohio Governor John Kasich, had also rushed to Balderson's aid.
Trump won the district by 11 percentage points in the White House race in 2016. Republican Pat Tiberi won re-election to the House by 37 percentage points but resigned before finishing his term, triggering the special election.
O'Connor, who did not concede on Tuesday, and Balderson will face off again in November to serve a full two-year term.
"The fight continues," O'Connor told MSNBC in an interview on Wednesday, declining to say whether he would seek a recount if one was not automatically triggered. "We're going to be sprinting."
The Ohio secretary of state's office said it could not yet declare a winner. Under state law, absentee and provisional ballots cannot be counted for 11 days with an automatic recount if the margin of results is within 0.5 percent of the votes cast.
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.
(Reporting by John Whitesides and Brendan O'Brien; additional reporting by Susan Heavey Editing by Bernadette Baum and Jonathan Oatis)