One Nation, an outside group that boosts GOP candidates, is placing its first advertising buy this cycle in Michigan’s Senate race, which pits incumbent Democrat Gary Peters against Republican challenger John James. 

One Nation, a nonprofit organization affiliated with the GOP super PAC Senate Leadership Fund, has reserved $4.5 million in television, cable and radio time to begin running Wednesday. 

“One Nation is going on offense to promote conservative policies in Michigan that will accelerate our economic recovery and provide opportunities to thousands of Michiganders,” said the group’s president Steven Law in a statement.

The ads come during a week when Peters’ profile will be on the rise both at the Democratic National Convention and in a Friday hearing of the Homeland Security and Governmental Affairs Committee. The committee, where Peters is ranking Democrat, is probing the U.S. Postal Service’s finances and operations during the pandemic and in the upcoming elections.

At the convention, Peters was slated to join an auto worker in casting the Michigan delegation’s votes to nominate former Vice President Joe Biden for president on Tuesday. On Thursday, he’s due to join a convention event with the group VoteVets. He will also speak on Thursday at a virtual Michigan for Biden event, according to an advisory sent by his campaign. 

Most polling through the summer has had Peters up by, in some cases, a 10 point margin. Politico reported an internal poll of the James’ campaign showing James down by fewer than 5 points, coming after a story about how national GOP groups had retrenched in the state.  

James, a military veteran who is Black, has outraised Peters in recent quarters, but as of July 15, Peters reported holding nearly $12 million in the bank to James’ $9.2 million. 

Though this week’s effort is the first for One Nation, other outside groups have already invested heavily in the race, with about $16 million spent so far, according to the Center for Responsive Politics.