Steve Abbott, described “as the man behind the curtain” for U.S. Sen. Susan Collins, said Friday he hasn’t decided whether he will enter the race for the 1st Congressional District seat.

“When I say I’m undecided, I truly am,” he said in a phone interview. “I’m not trying to be coy. It’s a lot to think about.”

Abbott, who serves as Collins’ chief of staff, is described by fellow Maine Republicans as loyal, ethical, smart, and a former Harvard University football team captain.

He said he loves his job — he’s Collins’ top advisor — and splits his time between Portland and Washington.

Abbott, 45, said he hopes to make a decision this fall, but won’t make a formal announcement about his intentions until January.

“Everything’s so accelerated,” he said. “I think people are getting overwhelmed already.”

Abbott said he’s weighing personal, professional and political considerations.

“I don’t know if this will be the cycle for me,” he said.

If he joins the race, he’d be one of three Republicans vying for their party’s nomination in June.

As it is now, Republicans have two men to choose from: Dean Scontras of Eliot and Charlie Summers of Scarborough.

On Thursday, the Democratic field settled in at five with the entrance of state Sen. Ethan Strimling into the race with Mark Lawrence, Adam Cote, Chellie Pingree and Michael Brennan.

The seat is open because U.S. Rep. Tom Allen, a Democrat, is taking on Abbott’s boss in hopes of winning her Senate seat.