Sen. Sam Brownback, who is considering a White House bid in 2008, said Monday the Republican field has room for a "full-scale Ronald Reagan conservative" and pledged to make a final decision next month.

The Kansas senator said he was not discouraged from running by the Democrats' strong gains in this month's midterm elections, including majority control of the House and Senate.

"It does not make it less likely," he said in an interview. "I really believe that the basic conservative ideas and ideals were not repudiated. Our execution was."

A more daunting challenge for Brownback are the better known potential candidates. Arizona Sen. John McCain and former New York City mayor Rudy Giuliani have set up presidential exploratory committees. Massachusetts Gov. Mitt Romney and Senate Majority Leader Bill Frist, R-Tenn., also are weighing bids.

"I think there's room for a full-scale Ronald Reagan conservative in the field," Brownback said. "I fully agree that other people have much higher name identification than I do. No question about that. But I think what you have to look at is the policy positions they get out once you have an effective campaign."

Brownback, who was elected in 1996, is a forceful foe of abortion and embryonic stem-cell research. He also has taken a prominent role in the fight against genocide in Sudan's Darfur region.

Brownback has made several trips to Iowa, New Hampshire, Michigan and other states that hold early presidential nominating contests. While national polls show McCain and Giuliani running strong, similar polls have shown Brownback in the low single digits.

He dismisses the early surveys.

"Where are my positions and others versus the base of the party?" he asked.