PORTLAND – As the Oregon presidential primary gets closer many voters have said they are looking forward to casting their ballots.

The race gathering much of the attention appears to be between Sens. Hillary Clinton and Barack Obama, both are vying for the Democratic nomination for president.

“I’m more motivated to vote for Barack Obama so that’s why I’m interested in voting this year,” said Madeline Wilk, who just changed her party affiliation from unaffiliated to Democrat. “This year it is worth changing.”

Nancy Kelly, a registered Green Party member, was also in line to change her party affiliation to Democrat. “It didn’t really matter. I was Green Party, but I never voted for a Green Party member.”

Those two women are part of a growing trend.

According to the secretary of state’s office, 12,548 voters changed party affiliations in March. Of those changing parties 9,683 chose to be a registered Democrat, with 5,014 of those formerly independent voters.

Election officials said the state’s primary system is motivating much of the change.

“It’s a closed primary so you have to be registered as a Democrat or Republican to vote in either of those parties,” said Eric Sample with Multnomah County Elections Division.

To change political parties, voters must fill out a brand new registration card and chose a new party affiliation. The last day to change parties or register to vote is April 29.

“It’s pretty typical, you find that people switch back and forward it’s not unusual at all,” said Sample.

There is so much interest in switching parties, Sample said the elections office has been inundated with requests. Workers sit in a room processing the changes.

With neither Obama nor Clinton with enough delegates to secure the Democratic nomination, the May 20 primary is gaining in importance.

“I’m excited to be able to vote in a primary,” said Kelley.

Many Oregon voters, regardless of past party preferences, do not want to be left out of the political process.