“The response we’ve gotten from folks I’ve talked to has been very positive, but this is at a very preliminary stage,” FitzGerald said.

He currently serves as executive director of the Kentucky Resources Council, an environmental nonprofit, a position he said he'd relinquish if he decided to enter the race.

According to the Courier-Journal, FitzGerald lobbies on environmental and social justice issues at the Kentucky statehouse. He indicated he is waiting partly to see whether Secretary of State Alison Lundergan Grimes enters the race.

“It will be a decision I make with my family, with my extended family and with folks who have more experience in electoral politics than I,” he said.

Lundergan Grimes is considered by many Democrats' best option in the race, now that a handful of other potential candidates have declined a run. But it's unclear whether she'll decide to enter the race, as some believe she'd prefer to run for governor in 2015.

Democrats have yet to front a candidate to challenge McConnell.