DES MOINES – Former New York City Mayor Rudy Giuliani has accepted an invitation to join a presidential debate in Iowa in August sponsored by ABC News, his first major commitment to the state since bowing out of a straw poll later that month.

The debate is planned for Aug. 5 in Des Moines, and Giuliani joining the platform is likely to ensure that virtually all the other Republican contenders will join. Soon after Giuliani announced Wednesday he would attend the debate, former Massachusetts Gov. Mitt Romney also agreed to participate.

Most national polls have shown Giuliani leading other rivals for the GOP presidential nomination, though those polls have been flux in recent weeks.

Polls have also shown Giuliani running strong in Iowa, where caucuses begin the voting process. Giuliani has built less of an organizational presence than some of his GOP rivals in the state, and he rocked Republican politics last week by deciding to pull out of the Iowa straw poll.

The Republican Party of Iowa traditionally runs the straw poll in August before the caucuses in January, and those straw polls in past competitive election cycles have drawn flocks of candidates, who spend million courting Iowa activists in hopes of a strong showing.

Sen. John McCain of Arizona also bowed out of the straw poll.