Sen. Debbie StabenowDeborah (Debbie) Ann Stabenow10 Senate Democrats are up for reelection in Trump country At least Alzheimer’s research is bringing Washington together Senate Dems block crackdown on sanctuary cities MORE (D-Mich.) continued her strong and consistent fundraising pace by bringing in just shy of $1.5 million in the last three months, and used that to purchase $3.25 million worth of television ads in the state this fall, her campaign told The Hill on Monday.

Stabenow, who also raised $1.5 million in the last quarter, now has $4.5 million in the bank after paying for the TV ads. The significant investment in air time comes as Michigan appears to be in presidential contender Mitt Romney's cross-hairs, meaning an increased demand for air time in the fall and a ratcheting up of prices. Michigan also has a number of competitive ballot initiatives that deep-pocketed interests are likely to spend on.

While most swing-state Democratic senators are facing tough races this year, it looks increasingly like Stabenow will be safe. She'll face the winner of an Aug. 7 primary between former Rep. Pete Hoekstra (R-Mich.), whose campaign has struggled, and businessman and philanthropist Clark Durant (R). Neither Republican has released his fundraising totals for this quarter, which spans from April through June.

The Hill rates the race as leaning Democratic.