Powell has shared his military and diplomatic expertise in meetings with Democrat Barack Obama and Republican Rudy Giuliani, his spokeswoman, Peggy Cifrino, said Tuesday. A planned meeting with Republican Mitt Romney earlier this year was postponed due to bad weather.
But when it comes to sharing his money, Powell chose McCain, the Republican senator from Arizona.
While not meant as an endorsement, Powell's $2,300 contribution last week gave a bit of needed cachet to McCain's struggling campaign.
"General Powell has known Senator McCain for many, many years, he considers him a friend," Powell spokeswoman Peggy Cifrino said, adding: "It was not a formal endorsement and he has not endorsed any of the candidates."
In a June appearance on NBC's "Meet The Press," where he acknowledged meeting twice with Obama, Powell said: "I make myself available to talk about foreign policy matters and military matters with whoever wishes to chat with me."
Cifrino also noted that Powell is a Virginia neighbor of former Sen. Fred Thompson, who is contemplating entering the Republican race. The two, however, have not had a formal sitdown on policy issues, she said.
McCain also got a boost from former Commerce secretary and top GOP fundraiser Robert Mosbacher, who joined the campaign as general co-chairman.
McCain spokeswoman Jill Hazelbaker said Mosbacher has a similar role as former Sen. Phil Gramm of Texas, the other general co-chairman of the campaign. The two offer strategic counsel and serve as the grey eminences of the campaign.
Mosbacher, 80, is a Texan who served in the Cabinet of the first President Bush. He is a highly regarded fundraiser who served at the top echelons of George H.W. Bush's presidential campaigns.