Arkansas Senator Mark Pryor has said that he is in the “undecided category” on the issue of whether gay men and lesbians should be allowed to marry.

Pryor is among the final four Democratic senators who remain opposed to marriage equality after a flurry of senators shifted their public stance in recent weeks. The other three holdouts are Mary Landrieu of Louisiana, Joe Manchin of West Virginia and Tim Johnson of South Dakota.

“I would put me down in the undecided category,” Pryor told 5News on Friday. “I did talk with some friends of mine in the gay and lesbian community over the last week or so. We talked about this issue. We also talked about a question I received in the office not too long ago where they asked whether being gay was a choice or whether you were born that way. I told them, I said, 'Honestly I've never really thought a lot about that.' Maybe a lot of people think about that. I haven't spent a lot of time thinking about that. But one of the things I hear from them is they feel very strongly that it's not a choice for them, and I respect that. I'm not going to dispute that. I appreciate that, and I appreciate their honesty. For a lot of these people they just really open their heart to me and talked about some of the struggles they've had over the years with their sexual orientation. I respect that and appreciate their patience, and I appreciate their honesty.”

(Related: Sen. Mary Landrieu personally backs gay marriage but obliged to represent Louisiana.)

On Thursday, Florida Senator Bill Nelson said that he could not discriminate against gays because “The Lord made homosexuals as well as heterosexuals.” The following day, Indiana Senator Joe Donnelly said that backing the institution was “the right thing to do” and North Dakota Senator Heidi Heitkamp said that the “importance of family is enduring” in announcing her support.

Fifty-three senators support marriage equality, including two GOP senators: Rob Portman of Ohio and Mark Kirk of Illinois.