BOSTON — After a year of mulling his political future, Scott Brown, the former senator from Massachusetts, has told people on Capitol Hill that he intends to open an exploratory committee and run this year for the Senate from New Hampshire, according to people with firsthand knowledge of those discussions.

National Republicans have been urging Mr. Brown to get into the race, believing he would pose a formidable challenge to Senator Jeanne Shaheen, a freshman Democrat who is seeking re-election, and would help the party in its quest to capture control of the Senate.

Mr. Brown has told associates that he intends to announce soon that he is forming an exploratory committee for his candidacy, said people close to him, who spoke on the condition of anonymity because they were not authorized to speak for him. Forming such a committee would allow him to raise money and organize a campaign staff, but it could also force him to terminate his contract with Fox News, where he is a commentator.

He is scheduled to speak on Friday at a state Republican event in Nashua, N.H., and could use that occasion for an announcement.