He will, the real question is if he wants to challenge Markey or Warren, Markey is very old and Baker os much stronger than Scott Brown, but polarization is a lot higher. If he did successfully pull it off, he would be DOA in 6 years, I could see him staying as Governor, moving to Nantucket and running for that district in a red wave, especially after Keating retires. I doubt, that he wants to be Governor for 30 years, but he can, if he wants, if he wants higher office, is really the real question
Ask Senator Bill Weld how that went for him.