The three rivals for the 2006 governor's race continue to walk a fine line between highlighting their differences and promoting their shared GOP beliefs.

Last Tuesday, state Auditor Betty Montgomery and Secretary of State Kenneth Blackwell wasted little time lambasting a third opponent's choice for a running mate.

Attorney General Jim Petro, in a bid to woo conservative voters, tapped Hamilton County Commissioner Phil Heimlich, whose alliances include the group that successfully pushed Ohio's gay marriage ban, one of the country's toughest.

''This Heimlich maneuver will not save Jim Petro's last-place campaign from choking,'' quipped Mark Weaver, a Montgomery strategist and spokesman.

Blackwell said Petro was trying to do ''through mergers and acquisitions what he cannot do on his own, and that is consistently champion conservative principles and policies.''

Yet two days later, Heimlich, Montgomery and Blackwell were in the same crowded Statehouse hallway denouncing plans to expand gambling in Ohio. Petro was out of town but earlier in the week publicly spoke against bringing casinos to the state.

''It's a very, very tricky time to maneuver their way toward the nomination,'' said Paul Beck, an Ohio State University political scientist.

The candidates know they have to set themselves apart from one another to win the nomination, he said. On the other hand, they can't be so negative that they might lose GOP voters in the general election.

''They don't want to be on the wrong side of an issue that most of the supporters of their party feel strongly about, and they don't want to give their opponents in the primary any ammunition to attack them,'' Beck said.

Blackwell, the most conservative of the three candidates, said through a spokesman Tuesday's comments and Thursday's coziness were compatible.

''Being opposed to political identify theft on one day and in favor of stopping the expansion of state-sponsored gambling on another is consistent,'' said Blackwell spokesman Carlo LoParo. ''It's nothing to do with issues, and everything to do with inconsistencies demonstrated by the attorney general.''

A Petro spokesman said he was disappointed by Blackwell and Montgomery's Tuesday comments criticizing his running mate, but Thursday's news conference was another matter.

''They need to say what they need to say for their campaign purposes,'' Matthew Cox, a Petro campaign consultant, said Friday. ''But for the issues presented yesterday (about gambling), they can all stand together.''

The Montgomery camp brushed off the discrepancy.

''It's like any family, where there are disagreements and agreements,'' Weaver said. ''People pay a lot of attention to a governor's race. They can weigh the differences and similarities pretty well.''

Democrats said the differences reflect how badly the three candidates want to be governor.

''What's true, the Tuesday comments or the Thursday comments?'' said Dan Trevas, a spokesman for Columbus Mayor Michael Coleman, who is seeking the Democratic gubernatorial nomination. ''Do they like the guy or do they not? They'll say anything to get ahead.''

Cox downplayed the attacks on Heimlich, likening it to maneuvering among primary candidates in the most recent presidential election.

''Just like John Edwards was critical of John Kerry and then was his running mate, when it becomes clear one candidate is the front runner, or one candidate wins the primary, all Republicans will need to work together for common values, which is defeating Democrats, defeating gambling initiatives,'' he said.

Heimlich said he was taking Montgomery and Blackwell's comments to his selection as a compliment on his strength as a candidate.

''I joined the ticket because I believe in Jim Petro,'' he said. ''I participated in the press conference because I'm staunchly opposed to gambling. I can't explain why Betty or Ken reacted the way they did.''

Andrew Welsh-Huggins is statehouse correspondent for the Ohio Associated Press.