Former Pennsylvania Gov. Tom Ridge just said that opting not to run for the Senate next year was the "toughest personal, political decision [he has] ever had to make."

Ridge, who announced earlier Thursday that he would not run against newly minted Democratic Sen. Arlen Specter next year, appeared on MSNBC's "Hardball" Thursday evening.

The former governor said he will continue to work for the party as a private citizen and said that the GOP must make changes if it wants to win back a majority in Congress.

"Our message became shrill," he said of the GOP. "We became very divided over these social some point we will have to become less judgmental."

Ridge said the Republican Party needs to return to specific fundamentals like limited and competent government.

Quizzed on former Rep. Pat Toomey, now the leading Republican in the Senate race, Ridge said he didn't know if Toomey could beat Specter.