The Washington State Democratic Party is throwing its weight into the King County executive race, spending $47,000 on mailings supporting Dow Constantine and opposing Susan Hutchison, according to the party.

At the same time, an independent TV ad campaign attacking Hutchison received a $70,000 boost from the Service Employees International Union, while a business-backed group running a TV ad attacking Constantine has spent an additional $50,698.

Total independent expenditures in the race have topped $500,000, while the candidates have raised more than $1.6 million total. Constantine is leading in campaign fundraising and in support from independent expenditures.

The Democratic Party's mailings, reported to the state Public Disclosure Commission as in-kind contributions to the Constantine campaign, continue familiar themes, saying "Conservatives like what they see in Susan Hutchison," and accusing her of trying to "hide her true beliefs."

"We've said all along that she's the Republican in the race and Dow's the Democrat in the race. This has been a top priority for us all along," Democratic Party Chair Dwight Pelz said Friday.

Constantine, chair of the Metropolitan King County Council, is a self-professed Democrat. Hutchison, a former TV news anchor who now runs an arts and science foundation, doesn't acknowledge a tie to either party. Party labels, for the first time, aren't on ballots this year. Voters approved an initiative last year that made the office nonpartisan.

Hutchison's campaign chair, Jordan McCarren, said although Constantine has raised more money, "We were able to spend considerably more this final week on television. He managed his campaign much like he managed King County government -- inefficiently and overspending."

Constantine campaign spokesman Sandeep Kaushik took issue Saturday with McCarren's claim that Hutchison has spent more on ads. He said Constantine has spent more and lined up ads that are reaching more viewers than Hutchison.