He received more than 50% of the votes from members of the state central committee of the Colorado Democratic party reports the Denver post.
"I'm very excited," Palacio said after the vote. "I'm excited for our party. We have a lot of work ahead of us as Democrats. I look forward to working with Democrats from all 64 different counties to make sure that we succeed in 2012."
"This is a serious time. We've got families all across this state that are looking for work, or who are making less than they were 10 years ago," Sen. Michael Bennet said after Palacio's win.
"We've got serious challenges. And we need to approach that with a serious voice, and I think he (Palacio) will be that voice."