ALTOONA, Iowa — Five of the Republican presidential hopefuls came to wish Gov. Terry Branstad a happy birthday Saturday night at a theme park here as the Iowa governor celebrated his 65th birthday.

As he is one of the most influential Republicans in the state and his is an endorsement all of the candidates would love, those who want to win the Jan. 3 caucuses came to kiss his ring, but one was noticeably missing.

Mitt Romney missed both the party and a forum sponsored by a Christian conservative group tonight in Des Moines, instead choosing to hold a town hall in New Hampshire. Despite opening up his headquarters this week in Iowa, he has chosen to skip the traditional campaign cattle calls and tonight was no different.

Branstad said he thinks “Iowans like to see the candidates” and he wished Romney and Gov. Jon Huntsman had made the trip.

“I would’ve preferred if Mitt Romney had came, had come to the event. Of course former Governor Huntsman hasn’t spent hardly any time in Iowa, and I think they’ll, you know I think they’ll regret it,” Branstad told ABC News, talking about the Family Leader Thanksgiving forum.

“I think that they need to spend more time here. I’m assured that Romney is intending to be back this coming week and spend a lot more time here, but I think you can see Iowans are looking for leadership that will get our fiscal house in order as a nation,” Branstad added, before praising the candidate that has been working the hardest to win the caucuses, Rick Santorum.

“I give Rick Santorum credit. He’s already been to all 99 counties. And I think that’s a challenge the other candidates — every time I ran for governor I went to every county and as governor, even when I’m not on the ballot, I go to every county every year,” Branstad said. “It’s not too late. The voters are going to go to the Iowa caucuses on Jan. 3, but there’s only so many days left, so it’s important for the candidates to take it very seriously.”

During his remarks, Santorum thanked Branstad for his 99-county campaign advice.

Although Romney didn’t make it, his senior advisor Ron Kaufman was in attendance, saying that he wasn’t here representing Romney and instead because he’s an “old friend of Branstad’s.”

Kaufman said the decision to open up campaign headquarters here was because “we are getting closer to Jan. 3.”

“We are playing in every state. We are organizing here and in Idaho. We are organizing in New Hampshire and New Mexico. We are organizing in all 50 states,” Kaufman said.

The night was mostly about wishing the governor a happy birthday and heaping praise on the governor of the first nominating state, a lighter event in the midst of the political cycle.

“I’m so happy that Iowa doesn’t have a mandatory retirement age for governor,” Rick Perry said. “You’re never going to retire.”

Branstad was governor of the state for 16 years before taking a 12-year break, getting re-elected last year. He also celebrated his 39th birthday at Adventureland.

Perry, Santorum, Herman Cain, Ron Paul and Michele Bachmann came to the party after the forum. Newt Gingrich, who was at the forum, was expected to also address the crowd, but arrived much later than the other candidates and missed the event. He told ABC News he was sorry he missed it, but “got tied up at the other thing.”

Bachmann told the crowd that she wasn’t sure “what more I can do to identify” with Branstad and Iowa, because she was “born here” and “raised here,” so she bought an accessory for which Branstad is famous.

“I went out and went to my local mustache store,” Bachmann said holding up a fake mustache. Branstad is well known for his signature facial hair and attendees were sporting the faux facial hair at Adventureland.

Cain said the governor “could have been in cruise control, but he’s not. He’s still serving the people of this great state.”

One of the funnier moments of the night was when Paul threatened to serenade the crowd. Paul told Branstad that although he is both a doctor and a congressman he always wanted to be a singer, jokingly telling the governor and the crowd he was going to sing him happy birthday. He ended up not going through with it.