Democratic Pennsylvania Sen. John Fetterman said he would vote to confirm his colleague Sen. Marco Rubio (R-Fla.) as secretary of State if selected by President-elect Trump.

“Unsurprisingly, the other team’s pick will have political differences than my own. That being said, my colleague @SenMarcoRubio is a strong choice and I look forward to voting for his confirmation,” Fetterman wrote in a Tuesday morning post on the social platform X.

The news of Trump’s expected nomination of Rubio as his top diplomat came Monday. Rubio, who ran against Trump during the 2016 Republican primary, was at one point in consideration to be the president-elect’s running mate. Ultimately, Trump chose Sen. JD Vance (R-Ohio).

The Florida senator is expected to be confirmed in the upper chamber. His appointment will shrink the GOP majority in the Senate until Florida Gov. Ron DeSantis (R) appoints a replacement.

Rubio, who is on the Senate Foreign Relations Committee, is seen as tough on Iran and China.

Apart from Rubio, Trump has quickly filled out some of his national security posts, selected Rep. Elise Stefanik (R-N.Y.) as his ambassador to the United Nations and Rep. Mike Waltz (R-Fla.) to be his national security adviser.

Rubio, who was first elected to the Senate in 2010, has even received praise from some vocal Trump critics. Former Rep. Adam Kinzinger (R-Ill.) characterized Rubio’s selection as “pretty good.”