Environmentalists are typically part of the Democratic base but in Florida they're rallying to Gov. Charlie Crist (I).
Robert F. Kennedy Jr., an environmental lawyer and activist, announced he's supporting Crist's Senate bid at an event in Deerfield Beach Wednesday.
Last week, the Sierra Club announced it was co-endorsing Democrat Kendrick Meek and Crist.
"Crist has demonstrated his commitment to the environment through his service as governor of Florida, advancing a strong environmental agenda that included land acquisition and preservation in the Everglades Agricultural Area," the environmental group said in a statement.
Meek rejected the group's endorsement as a result of their split backing.
Meanwhile on Tuesday, California Gov. Arnold Schwarzenegger (R) announced via Twitter he's backing Crist.
The latest Quinnipiac University poll out Wednesday has Republican Marco Rubio at 44 percent, Crist at 30 percent and Meek with 22 percent.