However Boren has said the Illinois Senator will have his vote both at the Democratic convention in Denver in August and in November on election day.
Calling Obama "the most liberal senator in Congress", Boren criticised his record on working with Republicans saying "it does not reflect working in a bipartisan fashion" and has joined Florida Rep. Tim Mahoney in refusing to endorse the presumptive Democratic nominee.
Image: Official picture of Dan Boren. Credit: Public Domain
Boren, who described his congressional district in Oklahoma as "conservative" said to AP:
"I've got to reflect my district. No one means more to me than the people who elected me. I have to listen them."He follows Rep.Tim Mahoney of Florida who has announced he will remain an uncommitted delegate to the convention in August.
"I think this is an important time for our country. We're facing a terrible economic downturn. We have high gasoline prices. We have problems in our foreign policy. That's why I think it's important," he said in a telephone interview.

Mr. Boren, Aren't you a disgrace to your party? If you don't vote for Obama that makes you a racist.
Mr. Boren, Aren't you a disgrace to your party? If you don't vote for Obama that makes you a racist.
Hello and thanks for your comment...certainly does look as if Boren is catering to his "conservative" heartland