JEFFERSON CITY, Mo. (AP) -  Missouri election officials expect one-quarter of registered voters to cast ballots in Tuesday’s primary elections.

The voter turnout projections released Friday by the secretary of state’s office are compiled by estimates from local election officials.

The statewide forecast of 25 percent turnout would be fairly typical for recent primaries.

Two years ago, about 23 percent of registered voters cast ballots in the primary.

This year’s election features a spirited Republican primary to challenge Democratic U.S. Sen. Claire McCaskill, as well as contested races for other statewide offices and legislative seats.

Recent primary turnout peaked at 35 percent in 2004.

That year’s ballot included a constitutional amendment banning gay marriage and a hotly contested Democratic gubernatorial primary in which state Auditor McCaskill defeated Gov. Bob Holden.