Topeka ? Leading Republican candidate Sam Brownback on Tuesday introduced conservative state Sen. Jeff Colyer as his running mate in the Kansas governor’s race.

Colyer, from Overland Park, has become a leading spokesman for conservatives in the Legislature on health care issues, and he’s voted consistently with them on issues such as the budget, taxes and abortion. He is a plastic surgeon who’s been active in a private relief organization, the International Medical Corps.

Brownback announced Colyer’s selection early Tuesday morning on Twitter.com, ahead of starting a two-day, eight-city tour of the state to introduce Colyer to potential voters.

“I’m proud to announce Dr. Jeff Colyer as my running mate!” Brownback’s campaign tweeted. “He is a biz owner, statesman and humanitarian.”

Brownback, a U.S. senator who’s giving up his seat to run for governor this year, is favored to win the governor’s race in GOP-leaning Kansas. Democratic Gov. Mark Parkinson is not running.

Prominent Republicans had expected for days that Colyer would be named as Brownback’s running mate. Brownback was beginning his tour with a rally at an Overland Park shopping center — a strong hint that his choice for lieutenant governor was from vote-rich Johnson County.

Brownback and Colyer also planned to travel to Topeka later Tuesday for a rally and to file with the Kansas secretary of state’s office, a step necessary to guarantee their spot on the Aug. 3 primary ballot.

In the primary, Brownback faces Derby resident Joan Heffington, a former home builder and founder of a nonprofit group that attacks what she views as corruption among attorneys. The leading Democratic candidate is state Sen. Tom Holland, of Baldwin City.

Colyer first gained attention for his relief efforts with the International Medical Corps. In 2002, he ran unsuccessfully for the GOP nomination in the 3rd Congressional District, centered on the state’s portion of the Kansas City metropolitan area.

In 2006, he won a seat in the Kansas House, and two years later, he was elected to the state Senate.

The Kansas Democratic Party criticized Brownback’s selection of Colyer. “The new Brownback ticket pairs the right with the far right,” said Kenny Johnston, executive director of the Kansas Democratic Party.

“Instead of creating a balanced ticket Sam Brownback has chosen a right-wing millionaire who will help re-write his record of failure and extremism in Washington,” he said.