Former President Donald Trump made a fiery appearance in Vandalia, Ohio, on Saturday to rally support for Republican Senate candidate Bernie Moreno. As the contentious primary race approaches its climax, Trump seized the opportunity to attack Moreno's rival, state Sen. Matt Dolan, whom he labeled a "RINO" and criticized for his family's Major League Baseball franchise, the Cleveland Guardians, changing its name.

During his 90-minute speech at the Dayton International Airport, Trump passionately endorsed Moreno, describing him as a "fantastic guy." However, he lambasted Dolan, accusing him of being easily influenced by "woke left-wing lunatics" for supporting the name change from the Cleveland Indians to the Cleveland Guardians. Trump sought the crowd's opinion on the rebranding, which received a strong response in favor of the old name.

Dolan's emergence as Moreno's strongest opponent has intensified the battle lines in the primary, pitting Trump's MAGA supporters against Ohio's old-guard conservative establishment. Dolan's recent endorsements from Governor Mike DeWine and former Senator Rob Portman have further solidified his position as the leading contender, despite being considered more moderate than Trump's political ideology.

The Ohio Senate primary has attracted significant attention as it is the first competitive 2024 Senate primary where Trump has publicly endorsed a candidate. This, combined with Trump's two victories in the state by 8-point margins, has raised the stakes for him. Tuesday's primary results could have profound implications for Trump's influence in future tough races.

Although few independent polls have been conducted, recent surveys indicate a tight race between Moreno and Dolan. The intensity of the race reached new heights after an Associated Press (AP) report revealed a potential link between a Moreno email address and an account with Adult Friend Finder, a website known for arranging sexual encounters. The report, which the AP did not independently verify, sparked controversy and provided Dolan and his supporters with ammunition against Moreno's candidacy.

Dolan's aligned Buckeye Leadership Fund wasted no time in releasing a new ad that emphasized the controversial aspects of the AP report. The ad draws attention to the allegations and highlights Democrats' alleged involvement in promoting Moreno to ensure Senator Sherrod Brown's re-election.

While Dolan sidestepped questions about the AP report, Ohio Secretary of State Frank LaRose was more vocal in expressing his concerns about Moreno's trustworthiness. LaRose has struggled to compete financially against the independently wealthy Dolan and Moreno, relying heavily on an allied super PAC. However, that group, Leadership for Ohio, has shifted its focus to attacking the other candidates rather than supporting LaRose.

The primary race is entering its final days, with Moreno and Dolan directing their attacks mainly towards each other, seemingly overlooking LaRose. With ten TV stations reportedly refusing to air the Buckeye Leadership Fund's ad following cease-and-desist notices from Moreno's legal counsel, the race has taken a contentious turn.

Trump's surprise visit to Ohio became a pivotal moment for the Senate candidates, amplifying the already heated race. As the primary day approaches, the outcome will determine the future of the Republican Party in the state and potentially impact Trump's political influence moving forward.

(Note: The article is a summary of the provided context and does not include any fabricated information.