Jim Gibson will formally launch his campaign as the Independence Party's endorsed candidate for U.S. Senate today at the state capitol, joining the sizeable group of challengers for Republican incumbant Senator Rod Grams. Gibson won his party's endorsement for U.S. Senate with ease, but faces a daunting race ahead. The Edina-based software developer faces at least two competitors in his party primary, and party officials are hinting others may still enter the race. Minnesota Public Radio's Amy Radil reports.