Updated

President Trump predicted Wednesday that Republicans could ride a “giant Red Wave” into the November midterm elections – with his help – as he claimed victory for several candidates he endorsed in the latest set of primaries.

Democrats are consistently leading in so-called “generic” congressional ballot polls, are widely seen as having the edge in the race for the House and have turned a slew of races in once-safe Republican districts into competitive contests.

But in most of those races, the Democratic candidates have come up short.

Trump seized on the trend Wednesday morning as Republican state Sen. Troy Balderson held the lead over Democrat Danny O’Connor in Ohio's special election for a vacant House seat Tuesday. The race remains too close to call, but Trump and Balderson have claimed a GOP victory.

“The Republicans have now won 8 out of 9 House Seats, yet if you listen to the Fake News Media you would think we are being clobbered. Why can’t they play it straight, so unfair to the Republican Party and in particular, your favorite President!” Trump tweeted.

The president also highlighted how his endorsed candidates, including Balderson, outperformed the field in Tuesday’s races – and went on to claim that his personal campaign touch can lift Republicans over Democrats in other races across the country.

“As long as I campaign and/or support Senate and House candidates (within reason), they will win! I LOVE the people, & they certainly seem to like the job I’m doing. If I find the time, in between China, Iran, the Economy and much more, which I must, we will have a giant Red Wave!” he tweeted, after writing, “5 for 5!”

The score was a likely reference to five endorsed candidates either winning or leading the field as of Wednesday. Moments earlier, Kansas Secretary of State Kris Kobach, another Trump-endorsed pick, was shown in the lead in the unofficial tally for his state’s Republican gubernatorial primary – though that race has not been officially called either.

Elsewhere, Trump-backed candidates won in three Missouri and Michigan races.

It’s unclear how much Trump’s help boosted turnout for his favored candidates – but the president may have played a significant role in the reportedly high turnout in the Ohio contest by staging a rally in suburban Columbus on Saturday night.

O'Connor has not conceded, saying in a statement "we don't know the results quite yet."

Democratic leaders still contend that their ability to turn such races into competitive contests exposes Republican vulnerability in the fall.

Democratic Congressional Campaign Committee Chairman Ben Ray Lujan said in a statement he’s “never been more confident” his party can reclaim the House.

"That #OH12 is too close to call speaks volumes about @dannyoconnor1's strength and the GOP’s expensive, failed playbook. … #OH12 should have been a GOP slam dunk. That we are still counting ballots is an ominous sign for the GOP in November,” the DCCC tweeted.

Republican Party Chairwoman Ronna McDaniel, a staunch ally of the president, countered that “Troy Balderson's win tonight is another example of the so-called 'blue wave' being nothing but a ripple."

Fox News’ Gregg Re contributed to this report.