Updated: July 3, 8:20 a.m. | Former Massachusetts Sen. Scott P. Brown got Mitt Romney’s endorsement in New Hampshire Wednesday — but it might be a while until his comeback bid gets a lift from any of the Republicans seeking the GOP nod in 2016.

Typically, presidential hopefuls hustle to make inroads into the Granite State, which hosts the first primary on the national nominating calendar.

But the GOP’s 2016 prospects are so far staying away from that Senate race for fear of upsetting prickly Republican activists by endorsing Brown, who was a more moderate Republican in the Senate and supports abortion rights.

Brown is the odds-on favorite to win the Republican nomination on Sept. 9, when he will likely defeat former Sen. Robert C. Smith, R-N.H., and former state Sen. Jim Rubens. The GOP nominee will face Sen. Jeanne Shaheen, D-N.H., in November.

“I think you’ll see the hot presidential contenders stay away until the primary is over. It’s just safer,” said Charlie Arlinghaus, a veteran New Hampshire Republican operative.

Texas Gov. Rick Perry will travel to New Hampshire Aug. 22 and 23, but he has no plans to appear to with Brown or any other Republican Senate candidate. Perry endorsed a candidate in the contested Iowa GOP Senate primary.

Sen. Marco Rubio, R-Fla., declared himself “a strong supporter of Scott Brown” in a radio interview in early May, but he also cautioned twice, “we haven’t done anything formal yet.” Rubio endorsed three other GOP Senate candidates before their respective primaries in Iowa, Arkansas and Colorado.

New Jersey Gov. Chris Christie traveled to New Hampshire two weeks ago. The RGA Chairman endorsed a Republican candidate for governor but did not comment on the Senate race. Christie has not gotten involved in any Senate races this cycle.

That could be a smart move for the candidates. Brown is the favorite to win, but, Arlinghaus said, he “has a real issue with conservatives” owing to his moderate positions and voting record.

For example, in a 2012 ad for Brown, when he was running for re-election in neighboring Massachusetts, a woman declares, “Scott Brown is pro-choice.” He also said he would support an assault weapons ban after the massacre in Newtown in 2012.

Another 2012 re-election campaign ad showed Brown with President Barack Obama. The spot made sense when he was running to represent a more liberal state like Massachusetts; the same spot would be toxic for for Brown in a New Hampshire Republican primary.

Those positions are not popular with segments of the Republican primary electorate. For example, second Amendment groups have vocally taken him on about guns.

Despite this, Brown does not appear to be running away from his record. So far, his ads have focused on his personal story and ties to the Granite State, which he made his permanent residence several months ago.

Most recently, Brown’s campaign did not effusively cheer Tuesday’s Supreme Court ruling on the Hobby Lobby case like other Republicans.

“Scott Brown supports women’s health care and access to contraception but by injecting government into every aspect of our lives, Obamacare threatens all our freedoms. The best solution is to repeal it,” Elizabeth Guyton, Brown’s communications director, said in a statement to the Concord Monitor.

Instead of competing to be the “true conservative,” Brown, Smith and Rubens “have staked out different corners of the field and are pounding on their corners” as the right direction for the Republican Party, said state Sen. Andy Sanborn, who backed former Rep. Ron Paul, R-Texas, in the 2012 Republican presidential primary.

But Brown’s positioning gives Republicans looking to run as conservatives in 2016 a good reason to stay away.

“It would be a problem in New Hampshire for [a presidential contender] if they then came back here in the 2016 race, and they tried to run from the right, and the right’s going to say, ‘Yeah, but you endorsed this RINO in the primary,’” said former New Hampshire Attorney General Tom Rath, a former Romney campaign adviser.

Brown leads in public polling of the primary. A June survey from Suffolk University/Boston Herald showed Brown with 40 percent, Smith with 12 percent, Rubens with 4 percent, 38 percent of Republican voters in the poll said they were undecided.

New Hampshire Republicans predicted that the combined share of the vote taken by Smith and Rubens would climb higher than that.

“I don’t see a scenario where [Brown] wins with much more than 50, 55 percent of the vote,” said Dennehy, an advisor to Perry and to a Super PAC backing Rubens. “I don’t see that happening.”

It’s part of the reason why 2016 hopefuls are staying on the sidelines for now.

“While there could be tremendous upside by coming into endorse [Brown] and having him win, there’s not a lot of downside to playing it safe and staying neutral,” said Dennehy. Staying out, “you assure yourself of not angering those people” who did not support your candidate.

Their absence in the race strikes a contrast to the Iowa GOP primary last month. Three would-be presidential nominees actively campaigned for three different Senate candidates in the primary in the Hawkeye State, which historically hosts caucuses that precede New Hampshire’s primary on the presidential nominating calendar.

Rubio, Perry, and former Sen. Rick Santorum, R-Pa., stumped, cut ads, and cheered their respective candidates; Rubio picked the winner in Joni Ernst.

To be sure, Perry and Santorum both endorsed candidates who had backed their presidential bids in Iowa in 2012. Brown was not in New Hampshire for the 2012 primary, so nobody owes him any such favors.

And there is still plenty of time for presidential hopefuls to come in to help Brown: New Hampshire’s September primary is among the latest in the nation.

After the primary, though, New Hampshire Republicans expect the floodgates to open.

“I suspect we’ll see everybody at that point,” said Rath.

The race is rated Democrat Favored by the Rothenberg Political Report/Roll Call.

Clarification 8:25 a.m.

A previous version of this story omitted that Dennehy is an advisor for a super PAC backing Rubens.

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