Washington Gov. Christine Gregoire faces conflict-of-interest accusations as she enters the final three months of a tough re-election campaign.

The Democratic governor is battling GOP challenger Dino Rossi, who lost the governorship by fewer than 140 votes after two recounts in 2004.

But Rossi is crying foul over the involvement this year of the powerful Service Employees International Union.

Gregoire is getting a big boost in her campaign from the SEIU, which includes more than 30,000 state workers and is funding ads attacking Rossi. At the same time, Gregoire is involved with contract negotiations to decide the union members' pay and benefits.

"When you have one party, whether it's Republican or Democrat, that's in power for so long, you end up with the appearance of institutional corruption, and that's what this looks like," Rossi said.

The complaints don't stop there. State Republicans suggest there is a pattern that started with a deal Gregoire made with Indian gaming tribes, which helped bankroll the second recount that put Gregoire into office.

The governor had approved a major expansion of gambling but scrapped a provision requiring casinos to give the state a cut of the profits -- a provision demanded by every other state with tribal gaming.

"When you drive up a $2.7 billion budget deficit by treating those very, very well that contribute to your campaign and your re-election, that's where the red flags go up," Republican state Rep. Doug Ericksen said.

Gregoire and her campaign staff declined to comment, as did SEIU representatives and the tribal leaders.

Washington's Republican attorney general has said there was nothing illegal about the negotiations with the tribes or those with the union. But that hasn't kept the allegations out of the headlines.

"It's very important that the governor not have any appearance of impropriety, but at the same time the challenger will always attack the incumbent on those grounds," said Matt Barretto, political scientist at the University of Washington.

FOX News' Dan Springer contributed to this report.