Bill Hagerty (left) and Manny Sethi

The Republican primary for U.S. Senate is heating up as early voting is underway.

The top two candidates in polling and fundraising — former Ambassador Bill Hagerty and Nashville surgeon Manny Sethi — have spent recent days trading barbs and polls as they jockey to represent the GOP in the election to succeed retiring Republican Sen. Lamar Alexander.

In the second quarter fundraising period, Hagerty raised more than double ($978,227) the amount raised by Sethi, though the race has largely escaped the big spending of the 2018 race for another open Senate seat. The two are, however, continuing to advertise on local TV stations, as are self-funding doctor George Flinn and Byron Bush.

Though President Donald Trump has endorsed Hagerty, the race between Hagerty and Sethi has remained close, according to available polling.

The Sethi campaign put out internal polling that showed the race within the margin of error, while the Hagerty team’s polls showed the former ambassador, Republican fundraiser and commissioner of the Tennessee Department of Economic and Community Development with a 16-point lead.

A new poll — reportedly not funded by either candidate — shows the race within the margin of error.

“In summary, Bill Hagerty has a lead in the primary race for the U.S. Senate, but it’s not a secure lead against Manny Sethi,” the pollster wrote.

The Hagerty team is seeking to discredit the poll by pointing out connections between the Sethi campaign apparatus and the polling firm, and in doing so pointed to similar questions about a 2018 poll that showed then-candidate Bill Lee leading the Republican gubernatorial primary race. Lee ultimately won the race, and the poll correctly captured the order of the top three candidates. Much of Lee’s campaign team is now working for Sethi, though the governor has not endorsed a candidate.

The two camps have also bickered about past campaign donations, as Hagerty cut an ad highlighting a $50 donation Sethi made more than a decade ago via progressive payment processor ActBlue, while Sethi responded by highlighting Hagerty's past support for Democrat Al Gore and Republican Mitt Romney, a Trump antagonist.

Though the COVID-19 pandemic has stifled much in-person politicking this year, both Hagerty and Sethi have been on the road in recent days for public appearances. Sethi appeared with Kentucky Sen. Rand Paul over the weekend, and Hagerty has a joint appearance with Arkansas Sen. Tom Cotton scheduled.

Hagerty also held a telephone town hall with Trump on Friday night. Sethi, too, has pledged his loyalty to Trump, and even spoke at a Trump rally in Nashville before the campaign.

“You got a real primary here,” Trump said. “The other side’s spending a lot of money.”

In the Democratic primary, Nashville attorney James Mackler has continued to lead in fundraising and recently announced the launch of his first TV ad. Among the other candidates vying for the nomination are Memphis environmental activist Marquita Bradshaw, Nashville pastor and attorney Robin Kimbrough Hayes and Nashville attorney Mark Pickrell.

This post originally ran in our sister publication, the Nashville Post