WASHINGTON, D.C. -- The 111th Congress officially convened Tuesday, and with it Sen. Jeff Merkley became the newest federal representative of Oregon.

Merkley, who defeated incumbent Republican Sen. Gordon Smith in November, was to be sworn in by Vice President Dick Cheney, along with six other new senators.

Nine new senators will eventually be seated in the 111th Congress but a race in Minnesota and President-elect Barack Obama's Senate seat remain disputed.

Merkley served as the Oregon House speaker prior to his ascension to the U.S. Senate.

Portland Democratic Rep. Diane Rosenbaum assumed Merkley's position as interim state House speaker until Jan. 12, the opening day of the state's legislative session, when a new speaker will be chosen by lawmakers.

 More: Local, state leaders take oath of office

In Washington, Merkley said Congress should have an economic stimulus package on the president-elect's desk by the middle of February.

Some lawmakers wanted to get the $800 billion stimulus plan to Barack Obama by Inauguration Day, Jan. 20, but that is now considered unlikely.

Merkley says the economic crisis is serious, but it is more important to make sure the bill is well-thought and effective than to approve it quickly.

"Our nation faces many challenges right now: an economy in recession, our armed forces in two wars, global threats from climate change and the proliferation of nuclear weapon states. This is not the time for incremental change -- we need bold leadership and action to address these challenges," he said. "We need to immediately pass an economic recovery package to create living wage jobs and lay the groundwork for future growth."

Democrat Ron Wyden, the senior U.S. senator from Oregon, accompanied Merkley to swearing-in ceremony with the vice president.

The Associated Press contributed to this report.