Missouri US Sen. McCaskill files for re-election

JEFFERSON CITY, Mo. (AP) -- Sen. Claire McCaskill of Missouri has officially begun her re-election campaign, the first and only Democrat so far in a contest that has attracted several Republicans.

McCaskill was in Jefferson City on Friday to file for the August party primary in her bid for a second, six-year term.

Three prominent Republicans are also in the U.S. Senate race. They are former state Treasurer Sarah Steelman, of Rolla; U.S. Rep. Todd Akin, of suburban St. Louis; and St. Louis businessman John Brunner.

McCaskill said Friday she expects there will be a clear contrast between her and whoever wins the Republican primary.