MASON, Ohio (CNN) - As promised, Mike Huckabee sent John McCain an official request Tuesday for a debate.
"Now that the race for the Republican nomination is down to just the two of us, I believe this is the time for a real discussion about our vision for the future of this great country," the letter reads. "I encourage you to join me in a Lincoln Douglas-style debate so that voters can better understand our views on critical issues."
McCain had said earlier in the day that his campaign had never heard directly from the Huckabee camp about a debate, a suggestion the former Arkansas governor has been making for weeks.
"Our Democratic counterparts, Senators Barack Obama and Hillary Clinton, have had recent opportunities to underscore the differences in their positions. It seems only fitting to me that Republican primary voters are differed the same," the letter continues.
Huckabee's future in the race hinges on the primaries in Texas and Ohio next Tuesday and Huckabee asked that the debate take place before then.
He concludes, "Senator, let's lead by example and get the ball rolling. I look forward to hearing your thoughts on this idea and debating you in front of the American people."
- CNN Political Producer Alexander Marquardt