Is Scott Brown running in New Hampshire? He tweets a big hint.

Scott Brown, the former Massachusetts senator, has told insiders on Capitol Hill he plans to run for the US Senate again – but, this time, in New Hampshire. Friday afternoon he tweeted that he was leaving his position at Fox News.

Mr. Brown is expected to announce the formation of an exploratory committee to consider a possible campaign for the New Hampshire Senate seat, the Associated Press first reported Friday morning. He is scheduled to speak at 4:30 pm at a Republican event in Nashua, N.H., at which he could make the announcement.

Republicans lawmakers have been for months now pressing the fellow Republican to run for the New Hampshire seat against Democratic Sen. Jeanne Shaheen, a first-term incumbent. National Republicans have said Brown could be a serious challenger to Senator Shaheen after Conservative groups in the state have wobbled her fan base over the last year with attacks on her support for Obamacare.

In 2008 Shaheen defeated Republican incumbent John Sununu. Except for Shaheen, New Hampshire voters have picked Republican candidates in every Senate race since 1980.

Brown, a lawyer and until Friday a commentator for Fox News, first gained national attention as the winner of a special election in 2010 following the death of Massachusetts Sen. Ted Kennedy. But in a much-watched reelection bid he was ousted from the seat by Democrat Elizabeth Warren, who became the first female senator from Massachusetts.

For months, Brown’s prospective hat toss across state lines and into New Hampshire’s race has been a big “is he or isn’t he” question. He reportedly has frustrated national Republicans with his hedges on making a go for the seat, key to the party's efforts to get a Senate majority. He also lost support within the GOP when he reneged on plans to compete in the Jan. special election to replace John F. Kerry, now secretary of State, in the Senate, the AP said.

If Brown again doesn’t run for the Senate, after a media extravaganza on Friday over his potential jump into the race, it could cost him even more dearly within his party.

Before his tweet Friday that he was leaving Fox, which he would have to do in order to reenter politics, there were other significant signs that Brown – Cosmopolitan Magazine's “America’s Sexiest Man” in 1982 – was indeed gearing up to do battle in the Granite State.

This year, Brown packed up his Massachusetts home and moved full-time to his vacation home in coastal New Hampshire. He has also spent much of the last two weeks phoning major Republican state officials and GOP lobbyists, as well as taking on Republican staffers for a possible campaign, the AP reported.

Brown also mailed $29,000 worth of checks on Thursday to a slew of GOP committees, The New Hampshire Union Leader reported.

But will the Granite State have him?

Democrats appear worried that it might.

Ahead of a possible formal announcement of Brown’s bid, New Hampshire Democrats were already defending what they had reportedly thought would be safe seat against the possible Republican challenger, according to The New York Times.

“Scott Brown is for Scott Brown and the powerful interests that back him, not New Hampshire,” read a statement the group released Thursday.

“New Hampshire isn’t going to let Scott Brown and his big oil buddies like the Koch brothers buy themselves a Senate seat,” it said.

National Democrats have also already spent a total of $360,000 on television advertising against Brown over the last few weeks, the AP said.

Still, though initial internal GOP polls for the election had showed Brown and Shaheen as essentially tied, a more recent public poll gives Shaheen the edge, Politico reported.

If Brown does announce his candidacy, he must first win a primary in September.