IRVING, Texas — Michael Huckabee bowed to reality today and out of the Republican presidential race.

“We kept the faith,” he told his end-of-the-road rally today after Senator McCain clinched the nomination. “I’d rather lose an election than lose the principles that got me into politics in the first place.”

The genial conservative went out as he had campaigned all along, with a quip: “It’s time for us to hit the reset button.”

Mr. Huckabee won the leadoff Iowa caucuses, making him a sudden but short-lived sensation, and then seven other states: Alabama, Arkansas, Georgia, Tennessee, West Virginia, Louisiana, and Kansas. Meantime, Mr. McCain piled up big victories on his way to winning the prize on tonight.

The writing was on the wall for weeks, but the former Arkansas governor hung on until Mr. McCain secured the necessary delegates.

“We started this effort with very little recognition and virtually no resources,” Mr. Huckabee told supporters. “We ended with slightly more recognition and very few resources.”

The crowd laughed. “But what a journey,” he said. “What a journey. A journey of a lifetime.”

Mr. Huckabee rarely raised a negative word during the campaign about Mr. McCain, a man he clearly likes, and he called him tonight to congratulate him.

Mr. Huckabee said he extended “my commitment to him and to the party to do everything possible to unite our party, but more importantly to unite our country.”

Mr. Huckabee vowed: “We aren’t going away completely. We want to be a part of helping to keep the issues alive that have kept us in this race.”

An ordained Baptist minister, Mr. Huckabee spoke the language of the pastors and preached in their megachurches. He compared abortion to slavery and played up his opposition to gay marriage.

At breakfasts and large gatherings with national Christian leaders, Mr. Huckabee urged pastors to use their address books and e-mail lists to mobilize their flocks.

For a time, conservatives dissatisfied with Mr. McCain were drawn to Mr. Huckabee, but the party began to unite behind the likely — and now certain — nominee.

Mr. Huckabee displayed the common touch that came from a meager childhood in a little rented house with a father who worked two jobs in Hope, Ark., hometown of President Clinton.

He told working-class voters he understood their problems.

“When you grow up and life’s a struggle, you have a whole different understanding of what most people are going through,” he said in one ad. “Most Americans want their next president to remind them of the guy they work with — not the guy who laid them off.”

He played the bass guitar on the campaign stage, to rock and roll classics like “Mustang Sally” or “Takin’ Care of Business.”

In scoring largely Southern victories, Mr. Huckabee demonstrated limited appeal outside of his religious conservative base.

He was also a near novice on world affairs, which became evident after a few stumbles. At one point, he was caught unaware that the White House had released a report saying Iran had halted its nuclear weapons program.

Throughout, he went easy on Mr. McCain — but not their common rival, Mitt Romney.

Mr. Huckabee said he was proud that he and Mr. McCain ran a civil campaign. He told supporters in Columbia, S.C., the night he lost there, “Even though I’d like the outcome to be just a little different, I had rather be where I am, and have done it with honor, than to have won with the dishonor of getting there by attacking somebody else.”