PHOENIX - Texas Rep. Ron Paul is the first to file paperwork to run in Arizona's Republican presidential primary.
The filing period opened Tuesday and a crowd of about 20 backers filed the paperwork at the Arizona Secretary of State's office in Phoenix.
Secretary of State spokesman Matthew Roberts says other candidates are expected to file for the Feb. 28 primary election as the day passes.
Paul is one of the top contenders in the Jan. 3 Iowa caucuses. Others include former House Speaker Newt Gingrich, former Massachusetts Gov. Mitt Romney and Texas Gov. Rick Perry.
Other top GOP candidates include Michele Bachmann, Rick Santorum and Jon Huntsman.