(CNN) - Former Republican presidential candidate Mike Huckabee officially endorsed Marco Rubio's Senate bid Tuesday, becoming the latest conservative to break with the national party over the GOP Senate primary race in Florida.
"I had a chance to get to know Marco over the years, spent a lot of time in Florida with him. And I've never seen a more energetic, articulate, principled conservative as Marco Rubio," Huckabee said in a video posted on his Web site.
"Marco loves liberty. He loves the idea that people can work hard and maybe get to keep something of what they worked hard for. That's the difference," he added.
Rubio faces Charlie Crist, the popular Florida governor, for the nomination. Crist immediately won the support of the National Republican Senatorial Campaign Committee as well as a string of GOP leaders in Congress.
Conservative activists and bloggers have expressed disappointment the party was so quick to write off Rubio, a charismatic 38-year-old of Cuban descent whose quick rise in state politics and conservative credentials have won admiration from many in the party.
Huckabee's endorsement - first leaked accidentally more than three weeks ago - comes a week after South Carolina Sen. Jim DeMint also threw his support behind Rubio, declaring he was "convinced" the former Florida House Speaker could beat Crist.
Recent polls show Crist with more than a 30-point lead in the race, though primary voters won't head to the polls for more than a year.