It's pluses for all after initial round: top women all have reasons to be happy; Liukin leads over Kelley.(gymnasts Nastia Liukin and Natasha Kelley)

Byline: David Barron

Aug. 18--ST. PAUL, MINN. -- Women's gymnastics in the United States has become a marathon, with competitions leading to training camps, followed by more competitions leading to selection camps and the 2006 world championships -- and that's even before the final two-year run leading toward the 2008 Olympics in Beijing. With the length of that journey firmly in mind, each of the top-ranked senior women at the USA Gymnastics national championships had something to celebrate with Thursday's performances at the Xcel Energy Center. Nastia Liukin, the defending national champion from suburban Dallas, held the opening-day all-around lead and had the night's top scores on uneven bars and balance beam as she continued to tune up new elements in three of four events. Natasha Kelley, 16, of Katy, combined surprisingly difficult content with improving performance skills, moving past two world champions into second place in the all-around entering Saturday night's finale in her first seniors championships. Memmel bouncing back Defending world all-around champion Chellsie Memmel, who began training on uneven bars and…