HARRISBURG - "Pat Toomey / U.S. Senate" stickers blossomed on a clear majority of the lapels at the two-day Pennsylvania Leadership Conference, the annual gathering of the state's top conservative activists that concluded yesterday.

It's no secret that the former Lehigh Valley congressman is about to challenge Sen. Arlen Specter in the 2010 Republican primary, amid anger on the right at Specter's support for the $787 billion economic stimulus and other Democratic spending priorities.

In a keynote address to the group, Toomey fell short of a formal announcement, but he fired up a crowd of about 600 with a denunciation of the government's "lurch to the left." The passion to topple Specter even spilled over into the part of the program dedicated to hearing from three likely Republican candidates for governor.

First, an anonymous attack flier on all the tables listed former U.S. Attorney Pat Meehan's connections to "Liberal Benedict Arlen." Then, during a question-and-answer period, several audience members demanded to know where each candidate stood on the primary.

"We have our own situations we're worried about," joked Rep. Jim Gerlach (R., Pa.), who said he was there to discuss gubernatorial issues. State Attorney General Tom Corbett also passed.

"I'm not going to duck the question," Meehan said, adding that he had worked for Specter and would probably vote for him, though he does not always agree with the incumbent. "I'm sure he can stand on his feet and defend his record, as we are, and we should be judged on our own individual records," Meehan said. He earned a round of respectful applause from parts of the room.

The conference brought together activists from different elements of the conservative movement: homeschoolers, creationists, antiabortion groups, business interests, small-government libertarians. Organizers said this year's attendance was a record.

Earlier, Toomey said that Specter had to go because he had been complicit in programs that violated GOP small-government ideals.

"Now I don't often quote Barack Obama . . . but in this case I'll make an exception: It's time for change," Toomey told the crowd. "I believe that a Republican senator from Pennsylvania ought to stand up for the commonsense conservative principles that are at the heart of the Republican idea, that really are at the heart of the American dream."

He ran against Specter in 2004, coming within 17,000 votes of toppling him.

Toomey was preaching to the choir in the ballroom at the Four Points Sheraton in Harrisburg.

"The biggest problem I have with Arlen Specter is he's not defined," said Lou Petolicchio, an activist from Myerstown, in Lebanon County. "I can't trust where he's coming from. I don't know who he is. For the first four years of a term, he votes like Ted Kennedy, then for two he tries to show he's a Republican."

Peg Luksik, an antiabortion activist who ran for governor three times in the 1990s, already is in the race against Specter. She spoke on a panel about pro-family policies, and told reporters she would stay in the race. Some conservatives said they needed to rally around the one candidate with the best chance of winning, to avoid splitting the anti-Specter vote.

Luksik, 53, said that Toomey told her directly in February that he was not going to run against Specter and instead would try for governor. Some of her backers have suggested that Luksik was double-crossed, but she said yesterday that she would not regard Toomey's reversal as a betrayal.

"Believe me, I have five boys, so I understand that these two men have a long personal and rather vindictive history, and that there's a real desire for the two of them to go and hit each other with sticks," Luksik said. "I get that."