JEFFERSON CITY, Mo. -- Missouri residents waffling about whether to run for office have only a little more time to make up their minds.

Candidate filing for the August primary elections ends at the close of business Tuesday.

Already, nearly 500 people have filed with the Missouri secretary of state's office to run for the U.S. House or Senate, state Legislature, statewide offices or circuit judgeships.

Of Missouri's incumbent members of Congress and statewide officeholders, Democratic Secretary of State Robin Carnahan is the only one not seeking re-election. All of the incumbents face at least one challenger from another party so far.

Significantly more people have filed to run for office as Republicans than as Democrats.