But a battle was joined in 2003 over the issue of slot machines, with Mr. Miller and Mr. Ehrlich in favor of allowing them at racetracks. While Mr. Miller was an irresistible force on the issue in the Senate, strong-arming a bill through his chamber, he ran into an immovable object in the House. Personally opposed to slots and skeptical of a plan he considered a giveaway to the racetracks, Mr. Busch defeated the legislation that year. For the rest of his term, Mr. Ehrlich was unable to forge a plan that Mr. Busch and Mr. Miller could agree on. Not until Gov. Martin O'Malley, a Democrat, took office in 2007 was a deal on slots made.