But this is far from the standard political endorsement.
Just a few months ago Bramble announced his support for former Massachusetts Gov. Mitt Romney, as did 55 of his fellow Republican lawmakers.
McCain's campaign is expected to announce the endorsement Tuesday, but Bramble really switched sides some time ago.
"I think there is room at this stage of the presidential contest to consider several candidates," said Bramble, who does not want his support for McCain to be seen as a criticism of Romney. "I would have no problem if Gov. Romney was the party's nominee."
Bramble signed a Romney endorsement letter that circulated through the Legislature. He also went to a press conference but did not stand on stage with the candidate on Feb. 20.
Less than two weeks later, Bramble spent 45 minutes alone with McCain at the Grand America Hotel. At the end of the meeting, Bramble promised his support.
Bramble liked McCain's willingness to take tough stands that may not be popular. He cited McCain's support for the troop surge in Iraq and his involvement in an attempt to create an immigration reform package, which has since stalled in the Senate.
Bramble dismissed the Romney letter, saying it was not an endorsement, only a sign of support for a visit and fund raiser by Romney, a Mormon with Utah ties.
"I didn't see supporting Mitt's appearance the same as saying I was going to work on his campaign," Bramble said.
Other Republicans who signed the letter saw it differently.
Senate President John Valentine is one of the Legislature's biggest Romney supporters, saying he has had "more personal contact with Mitt" when he led the Salt Lake Olympic Organizing Committee.
Valentine said Bramble will be welcomed back to Romney's camp at any time.
"When John McCain doesn't make it through the primaries, we would sure like to have Sen. Bramble back on this side," Valentine said.
McCain's biggest supporters in Utah include Gov. Jon Huntsman Jr. and Attorney General Mark Shurtleff. Most public officials and, according to polls, most Utah Republicans are backing Romney.
In a recent ABC News-Washington Post poll 20 percent of Republican leaning voters support McCain, with 10 percent backing Romney. Former New York Mayor Rudy Giuliani leads the pack at 34 percent.