Massachusetts Republicans are desperately scrambling to find a strong Senate candidate to replace Scott Brown, with some even trying to persuade Mitt Romney’s wife or son to jump into the race to avert another electoral disaster.

Update: Tagg Romney: I’m not running for Senate

The former GOP senator’s decision to stay out of the June 25 special election surprised and angered some Republican leaders, who said it will make it much harder to beat a Democratic opponent without Brown on the ballot.

“I’ve had several people call me and ask about Ann Romney,” Ron Kaufman, a longtime friend and aide to the former Massachusetts governor and 2012 presidential candidate nominee, told the Herald.

Ann Romney’s inspiring battle against multiple sclerosis and her star turn on the GOP convention stage turned her into a popular national figure, especially among women voters in Massachusetts.

“That would be a very interesting thing. I would certainly love her to think about something like that,” said House Minority Leader Bradley Jones (R-North Reading).

But Kaufman said Mitt’s charismatic wife, who has never run for office, would be unlikely to take the plunge. “The timing is not great, and I don’t think she sees herself as a candidate,” he said.

Other GOP leaders also raised the prospect of Mitt’s eldest son, Tagg, launching a surprise Senate campaign. Tagg Romney was a close campaign adviser and surrogate for his father and is a successful businessman living in Belmont.

The push for a Brown substitute comes as frenzied Republicans are running out of time to find someone who could raise enough money and collect enough signatures to get on the ballot.

“Obviously, it’s not what anybody I talked to had hoped for … it’s daunting,” Jones said.

“Our bench isn’t too deep,” added Rob Willington, a former Massachusetts Republican Party executive director who’s worked with both the Brown and Romney campaigns.

Without someone such as Ann Romney, most Republicans agree the strongest candidate would be former Gov. William F. Weld, who just moved back to Massachusetts and hasn’t ruled out another run for office. Weld did not return messages, but sources close to him said he has “no interest” in running.

Former Lt. Gov. Kerry Healey was also being touted as a candidate, but sources said she also is unlikely to get in the race. Former state Sen. Richard Tisei, who narrowly lost a race for Congress in November, said he’s taking the weekend to consider running but said he has been more focused on another congressional bid.

“Scott caught everybody by surprise,” Tisei said. State Rep. Dan Winslow is also considering running and newcomer and former Navy SEAL Gabriel Gomez is expected to get into the race.

Brown released a statement saying he was too tired of the partisan bickering on Capitol Hill to make a third try for the Senate. Sources said he’s likely to take a job in the private sector.