US Senator Marco Rubio, a Florida Republican, visited the Boston waterfront Monday, telling the crowd there that he is seeking to “support four or five US Senate candidates,” House minority leader Brad Jones said. “He didn’t mention any particular candidates,” Jones said. The North Reading Republican tweeted a photo of himself with the Florida senator, and said he had “a quick 30 seconds” to meet him at the Boston Harbor Hotel. Former US senator Scott Brown was also at the event, Jones said. Jones said Rubio was raising money for a political action committee he created.