Excerpt- HELENA, Mont.: Supporters of long-shot presidential hopeful Ron Paul say the Montana Republican Party's quirky caucus rules could create an opening for their candidate that other states don't offer. Under the "closed caucus" system recently adopted by the Montana GOP, voting in the Feb. 5 caucus will be limited to about 3,000 Republicans who hold party posts, such as members of Congress, statewide officeholders and precinct captains. That includes hundreds of volunteer precinct posts that have long been vacant and that some candidates are now scrambling to fill with supporters. At least three presidential candidates — former Massachusetts Gov....