Though comfortably back in the Senate for another six years, Sen. Marco Rubio faces a tough political choice in 2018: partner or party?

With fellow Florida Sen. Bill Nelson up for re-election, and incumbent Republican Gov. Rick Scott his likely challenger, Rubio shied away Monday from commenting directly on the race, according to the Tampa Bay Times.

Nelson and Rubio have nurtured a good working relationship during their joint tenure in the Senate, despite representing different parties. When asked about 2018 by an Associated Press reporter, Rubio hedged, citing the need for party loyalty, but stopping short of endorsing a Republican challenge.

“I want us to have a Republican majority and grow that majority,” Rubio said. “But I have a good working relationship with Bill Nelson, so I’m not going to jump into an electoral argument right now.”

Scott recently put to bed rumors of his possible involvement in the incoming Trump administration, though the pair met in New York just last week. At the Republican Governors Association conference in Orlando last week, Scott said running against Nelson in two years was “an option.”

Scott endorsed Trump in March, the day after Rubio lost Florida’s GOP primary and withdrew from the presidential race.