JEFFERSON CITY – Republican state Sen. Will Kraus touted his support for a voter photo identification requirement Thursday while announcing his candidacy for Missouri secretary of state in 2016.

Kraus, of Lee's Summit, is the first to formally launch a challenge to Democratic Secretary of State Jason Kander. He said he plans to form an official campaign committee for the statewide office after the November general election, where he is unopposed for second Senate term.

Kraus – who represents District 8, which includes Blue Springs, Grain Valley, Oak Grove and Lee's Summit –  is perhaps best known as the sponsor of an income tax cut measure that the Republican-led Legislature enacted this year by overriding the veto of Democratic Gov. Jay Nixon. But he also has handled a variety of election bills, including the unsuccessful photo ID measure and a proposed constitutional amendment allowing a limited early voting period that will appear on the November ballot.

Among other things, the Missouri secretary of state oversees elections and business registrations.

"These are two passions of mine, and I believe I've led in the Missouri Senate on those issues," Kraus said. "I think this is a natural progression for me to move forward and try to advocate on a statewide basis."

Both Kraus and Kander served in the U.S. Army – Kraus deployed to Iraq as a helicopter pilot and Kander was an intelligence officer in Afghanistan – before entering politics by running for the Missouri House. Kraus served six years in the House before winning election to the Senate in 2010. Kander served four years in the House before winning election as secretary of state in 2012.

Kander has opposed a voter photo ID requirement, warning that it could disenfranchise thousands of currently eligible voters who don't have government-issued photo identification.

Kraus says a photo ID helps guard against the potential for people to fraudulently impersonate other voters, which has not been reported as a significant problem in Missouri. His proposal would allow people to obtain free state photo ID cards. People who are unable to get one would be able to cast provisional ballots, which would be counted if their signatures matched their voter registrations.

Kraus also has backed legislation making it easier for deployed military members to vote, shifting Missouri's presidential primary from February to March and abolishing the option for holding local elections in June.

On Thursday, Kraus criticized Kander's rollout of an online voter registration site in December. He said applicants' electronic signatures sometimes don't match the ones on file with local election authorities, and that Kander should have used an online registration process that still required signatures written on paper.

Kander said in an emailed statement that he has tried to ensure "that our elections are both secure and accessible" and "that it is as easy as possible to do business in Missouri." He also touted efforts by his securities division to protect seniors from financial fraud.