ALGONA, Iowa - A day after Mitt Romney compared Newt Gingrich's campaign to Lucille Ball's zany efforts in a chocolate factory, Gingrich went to an Iowa chocolate factory to challenge Romney on what he called his negative attack ads.

"Gov. Romney had a cute line yesterday about my team resembling Lucy and the chocolate factory and I just want to say: here I am in the chocolate factory," Gingrich said at The Chocolate Season in Algona.

Gingrich challenged Romney to debate him over the negative attack ads the Romney campaign and the super PAC supporting him released over the last month, which were believed to have contributed to a drastic drop in Gingrich's poll numbers in Iowa. The latest CNN poll put Gingrich, who was once leading in Iowa, in fourth place with only 14 percent support.

The semi-sweet barbs began this week after Gingrich's campaign failed to collect enough eligible signatures to make it on to Virginia's primary ballot.

Romney scoffed at the Gingrich misstep Tuesday, saying, "It's more like Lucille Ball at the chocolate factory. I mean, you know, you got to get it organized."

In a not-so-sweet retort today, Gingrich said, "Now that I have the courage to come to the chocolate factory, I hope Gov. Romney has the courage to debate me one-on-one and defend his negative ads. I don't expect him to do it, but I hope if he comes by, he at least buys some chocolates."

 Reenacting the famous chocolate factory scene from 1950's sitcom "I Love Lucy," Gingrich went to the back of the store to make chocolates. Gingrich and wife Callista dipped "tuttles" in chocolate.