NEW YORK (AP) -- While Republicans and Democrats are competing in Nevada and South Carolina this weekend, Mayor Michael Bloomberg's exploration of a potential third-party presidential campaign will take him to California and Texas, states that are rich in electoral votes. Texas also has the earliest deadline for getting on the ballot. Petitioners must file by May 12, but have a short window in which they can begin collecting signatures -- not until after the state's March 4 major party primary. Bloomberg will meet on Friday in Austin with Lance Armstrong and former surgeon general Richard Carmona, who is leading a coalition of health groups trying to get presidential candidates to address chronic health issues. Carmona, who served from 2002 to 2006 under President Bush, has not said which candidate he favors in the 2008 presidential race. He has said the coalition, The Partnership to Fight Chronic Disease, also will not make an endorsement. In California, Bloomberg will appear with Gov. Arnold Schwarzenegger at an event about infrastructure. The mayor says he is "not a candidate'' but associates told The Associated Press that he is conducting an elaborate state-by-state analysis to gauge his support.