In a state that has swung GOP in presidential elections since 1968 but has picked Democratic governors for 16 years, many Republicans think they finally have a candidate who can win back Indiana's top job.

Former White House budget director Mitch Daniels (search) brings a powerful political resume, and a matchup with Gov. Joe Kernan (search) in November likely would be the most expensive campaign in state history.

But Daniels first must win Tuesday's primary against conservative activist Eric Miller, who claims a grass-roots following of Christian conservatives and has run a spirited campaign.

"We've said all along that we don't need as much money as anyone else. We just need to get our message out," Miller said.

Both are running on themes of change, pledging to revitalize Indiana's struggling economy, reduce its $1 billion deficit and improve the operation of state government.

Republicans accuse Kernan and his predecessor, the late Gov. Frank O'Bannon (search), of a lax, mismanaged administration of a state that has lost more than 100,000 jobs in the past three years and has several state agencies facing allegations of criminal wrongdoing.

Kernan, who was lieutenant governor when O'Bannon died of a stroke last September, is seeking a full term as governor.

Daniels has the backing of most of the state's Republican leadership and had raised nearly $5.6 million as of early April, compared to just over $1 million for Miller.

Daniels was chief of staff for Sen. Richard Lugar, a political director for President Reagan, an executive at pharmaceutical giant Eli Lilly & Co., and most recently budget director under President Bush.

"If our state were in excellent shape, I would not be running," Daniels said. "This was not in my life's plan, but this is a time that calls on us to act and to work and succeed."

Miller founded an organization in 1980 called Advance America, which lobbies state government for what it calls pro-Christian issues.

He has been a formidable force on social issues, arguing against pornography, abortion rights and most any proposal backed by gays and lesbians. He has made a push for a state ban on gay marriage a primary campaign stand.

Miller is no longer leads Advance America, but he is banking on its grass-roots support, figuring that with traditionally low turnout on primary day, he can win with 200,000 votes.

While most political observers still consider Daniels the favorite to win Tuesday, no independent polls have been publicized in recent weeks.