Thousands of ballots poured into local election offices this week as Oregon voters make decisions in a hotly contested U.S. Senate race, the closely watched presidential race and several local races, and determine the fate of a long list of state and local measures.

Of Yamhill County's 50,526 registered voters, 13,600 had returned ballots as of Wednesday, putting early turnout at 27 percent mark. The rate was running 34 percent for Democrats, a little under 25 percent for Republicans and 19 percent for non-affiliated voters.

So far, the pace of returns statewide is running behind that of the 2004 presidential election. But state election officials said they still think Oregon will record a high turnout by the time next Tuesday's 8 p.m. deadline arrives.

That's based mainly on record voter registration for this year's election - a total of 2.17 million, fueled by a surge in Democratic signups.

The same phenomenon is apparent locally. Democrats trailed by more than 4,500 in November 2004, but have managed to cut that deficit to 1,700 with a flood of new registrations this year.

"All signs indicate there is very high interest," said Don Hamilton, spokesman for the Oregon Secretary of State's Office. "We still are expecting a very high if not record turnout in Tuesday's election."

Local Republicans and Democrats are each planning a last-minute voter turnout push, making sure those who haven't returned a ballot get one in on time.

"The Obama campaign is organizing a lot of that," said Will Neuhauser, who chairs the Yamhill Country Democratic Central Committee. "We're sort of piggybacking on that."

The latest state figures showed 522,188 ballots returned as of the end of the day Monday, or 24 percent. At this time four years ago, 30 percent of voters had returned ballots.

Hamilton said it's hard to know why the pace has been slower this year. But he said it could be because Oregon was actually a factor in 2004, while Republican John McCain wrote Oregon off at the outset this year.

Both George Bush and John Kerry made campaign stops in Oregon four years ago. But with polls showing Democrat Barack Obama with a big lead, neither Obama nor McCain has made general election stops this time around.

As a result, Hamilton said, voters might not feel any particular urgency to send in their ballots.

Neal Lockhart, who chairs Yamhill County's Republican Central Committee, said he was surprised at the low turnout so far. "It just seems like with such a big election, with so much riding on it, and you've got less then 30 percent with less than a week to go."

But he said Republicans tend to traditional in their voting habits, preferring to wait until Election Day.

"Ours are going to come in Monday and Tuesday," he predicted. In the end, he said, "I think it will be a good turnout."

After Thursday, anyone who hasn't mailed his ballot should hand-deliver it to the Yamhill County Clerk's Office or drop it in one of the drive-through dropboxes set up around the county. That's the only way to ensure it will arrive in time to count.

"If it's like the primary, we get pounded in the last few days," said Yamhill County Clerk Jan Coleman. "As early as you can get here, the better off you'll be. Try to do it early."

- The Associated Press contributed to this report.