DSCC spending $5 million against Collins in Maine?

$5 million buys a lot of media in Maine:

The Democratic Senatorial Campaign Committee has also made more than $15 million in buys in North Carolina, New Mexico, Minnesota and Maine, with the buys in Maine and North Carolina exceeding $5 million each. A committee official declined to comment.

Susan Collins, who is known to have a very thin skin, must be freaking out. There's no way the National Republican Senatorial Committee can spend anything like that to defend her.