Texas Sen. Ted Cruz, one of the Republican Party's most conservative members, launched his presidential campaign Monday in a crammed auditorium at America's biggest Christian university, becoming the first among what's expected to be a crowded field of White House hopefuls to officially enter the race.Texas Sen. Ted Cruz, one of the Republican Party's most conservative members, launched his presidential campaign Monday in a crammed auditorium at America's biggest Christian university, becoming the first among what's expected to be a crowded field of White House hopefuls to officially enter the race.