Ahead of the fall election, Senate Republicans’ political arm is making nearly $10 million in TV and digital ad reservations in Michigan, where it’s supporting former U.S. Rep. Mike Rogers of Brighton for U.S. Senate, according to a GOP source familiar with the total.

The sum is part of the first round of independent expenditures by the National Republican Senatorial Committee, which said it begin placing the reservations Thursday in four states: Michigan, Ohio, Nevada and Arizona. The ads would begin running in August, the source said.

The move is another signal national Republicans are serious about investing in Michigan’s Senate race this fall, even though the state isn’t considered a top-tier contest. Earlier this month, the NRSC announced it’s spending a seven-figure sum of money on a field program in the state to knock doors.

In the GOP primary on Aug. 6, Rogers is facing businessman Sandy Pensler of Grosse Pointe Park, former U.S. Rep. Justin Amash of Cascade Township and physician Sherry O’Donnell.

In all, the NRSC said it’s spending over $100 million on an ad strategy that will include independent expenditures and ad campaigns coordinated with candidates that target both a Democratic candidate and their party as a whole.

The group has already begun the coordinated campaigns with candidates in Montana, Pennsylvania, Maryland, Nevada and Arizona, and intends to launch similar coordinated buys with Rogers and Wisconsin’s Eric Hovde in the coming months, the group said.  

“Joe Biden’s extreme unpopularity has given us a chance to build a lasting Senate majority,” NRSC Executive Director Jason Thielman said in a statement. “We have the right candidates and the right message, now we need to execute.”

A pro-Rogers super PAC is on the air now in Michigan spending over $1 million to air ads featuring President Donald Trump praising Rogers, whom he’s endorsed, amid attack ads by Pensler about Rogers’ role in investigating the 2012 Benghazi terror attack in Libya a decade ago.

More: Pro-Mike Rogers group airs new ad amid hits from GOP Senate opponent Sandy Pensler

The NRSC’s counterpart, the Democratic Senatorial Campaign Committee in the spring announced a $79 million ad blitz including over $11 million in Michigan TV reservations to defend its majority in the Senate. The larger figure will also include coordinated ad buys with candidates.

The Senate Democrats’ initial reservations were more than double their initial buys last cycle, as they face a few open seats like Michigan’s, where Sen. Debbie Stabenow, D-Lansing, is retiring.

The DSCC, which is chaired by Sen. Gary Peters, a Bloomfield Township Democrat, also previously announced investments in staff on the ground in Michigan and eight other states. U.S. Rep. Elissa Slotkin, D-Holly, and the actor Hill Harper of Detroit are vying for the Democratic nomination.

“Michigan will be a competitive race. By definition, we’re a battleground state and battleground states are going to be a close election. But I’m confident we’re gonna win,” Peters told The Detroit News last month.

“Elissa Slotkin is obviously an incredibly strong candidate, and we’ll see what happens in the primary. But Michigan will will stay blue. We are going to reelect a Democratic candidate, especially since I chair the DSCC: We’re not losing Michigan on my watch.”

mburke@detroitnews.com