"I am not frustrated, bitter or surprised at the DSCC position. They are counting seats, and I am a number. Politics is a tough business, and national groups are seeking power," she said in an email to The Hill.

DSCC Chairwoman Patty MurrayPatricia (Patty) Lynn MurrayCDC director to miss fourth hearing because of potential ethics issues Week ahead: Lawmakers near deal on children's health funding Ryan suggests room for bipartisanship on ObamaCare MORE (Wash.) in a Tuesday conference call with reporters admitted that the DSCC has not endorsed in the Maine race. She said, however, that the DSCC has been in touch with people on the ground in Maine, indicating the group could change its mind as the race develops.

But that doesn't mean the national party apparatus would back Dill — it's remained mum on the race largely to avoid siphoning off votes from former Gov. Angus KingAngus Stanley KingMcConnell to Dems: Don't hold government 'hostage' over DACA Overnight Regulation: Regulators kill Perry plan to help coal, nuke plants | Senate Dems to force net neutrality vote | Maine senators oppose offshore drilling plan | SEC halts trading in digital currency firm Maine senators oppose Trump's offshore drilling plans MORE, who is running as an independent but is expected to caucus with Democrats if he wins.

Dill indicated that she believed such political calculus was behind the DSCC's continued silence on the race.

"I understand their interests are not aligned with mine, nor the voters of Maine. National political groups want a majority, but Maine people tell me that they want a U.S. Senator who is in touch with their day-to-day challenges," which is why she's running, she said in the email.

Though Murray declined to elaborate on the group's position in Maine, the DSCC did jump into the race on Tuesday with a $410,000 ad buy, which was announced last week after polling seemed to show King's lead over Dill and Republican Charlie Summers shrinking slightly. That's due in part to the $1.5 million spent by the National Republican Senatorial Committee and other Republican groups backing Summers.

Murray didn't play the party's hand on Maine, and said only that it was clear that the race had moved away from a solid win for Republicans and is now in play.

But the national party might be unable to keep quiet for long, as Democrats in Maine have in recent days expressed their support for Dill and irritation with those staying out of the race — a clear call for national Democrats to take a stance.

--This post was published at 3:36 p.m. and updated at 6:12 p.m.