Former Mayor Rudolph W. Giuliani said on Monday that he was seriously exploring whether he has "a chance" of winning the presidency in 2008, as he visited politically important Iowa and huddled with state advisers, donors to President Bush and other prominent Republicans. While Mr. Giuliani was officially in Iowa to attend two Republican fund-raisers, his behavior and remarks came close to politicking for himself. He ruminated openly about running, disclosed he was not sure what he would do if his friend John McCain also ran, and argued that if Republicans are to be a majority party, they need to...