When a flyer started showing up in 1st Congressional District mailboxes last week, attacking Suzan DelBene's business career, it seemed more a curiosity than anything else. The mailing was traced back to a Super PAC run by a Laura Ruderman supporter, but the initial $21,328.38 expenditure didn't seem likely to make a dent in a race where Darcy Burner led all Democrats in the polls, but DelBene would far outspend her opponents thanks the hundreds of thousands of dollars she'd already dumped into the race.

But after the third straight business day reporting expenditures, the $63,985.14 total is starting to amount to serious money, and raising questions about how much Super PAC cash Ruderman has behind her.

Up until last week this looked like a two-person race on the Democratic side, with Burner hoping her greater name ID and strong support within the Democratic base could fend off DelBene's huge money advantage and the unchallenged TV ad campaign it afforded her. It was hard to see a path for Ruderman in the primary. But if some so far undisclosed benefactor is willing to spend big on Ruderman's behalf, that could change the calculus.

Campaign finances being equal, I'm pretty confident Burner would make it through the primary to November. But I'm beginning to wonder if this race will turn out to be less a battle between candidates and more a battle between personal fortunes?