(CNN) - Iowa's Republican governor has a message for his party's presidential candidates: Come to Iowa more often.
"This is a state where you can effectively launch a campaign and it's not too late," Gov. Terry Branstad told reporters Monday morning. "We welcome the candidates to come to the Hawkeye state."
Branstad said the battle for the Iowa caucuses, which kick off the presidential primary and caucus calendar, are "wide open," adding, "it's a great opportunity."
Branstad added that former Arkansas Gov. Mike Huckabee's announcement Saturday that he will not make another bid for the White House "is momentus."
Huckabee grabbed 35 percent of the vote in the last caucus. His win in Iowa ignited the campaign, but Huckabee eventually dropped out of the hunt for the GOP nomination, which was captured by Sen. John McCain.
Branstad says "those (votes) are now up for grabs."
The top Republican in Iowa also pushed back against arguments that Republicans in his state will only vote for candidates who appeal to hard-core social conservatives. In an op-ed this weekend in the Des Moines Register, former New Hampshire GOP Chairman Fergus Cullen called for the candidates to stay away from the caucuses, saying that the dominance of social conservatives in Iowa has marginalized the state, saying "competing in Iowa has become optional."
Branstad told reporters that Cullen is wrong, saying "the truth is Iowa is a full spectrum state." And he used himself as an example.
The four-term governor from 1983 to 1999 ran for a fifth term last year, beating a more conservative candidate, Christian activist Bob Vander Plaats, in the GOP primary. Branstad went on to defeat the incumbent Democratic governor by ten points in the general election.
The state has seen a lot of presidential traffic this year. Newt Gingrich Monday kicks off a 17 city-and-state tour through Iowa. It's his first big campaign swing since formally announcing his bid last week.
Mitt Romney is coming to Iowa on May 27. It's the first visit to Iowa this cycle for the former Massachusetts governor and 2008 GOP White House hopeful. The day before Rep. Michele Bachmann of Minnesota returns to Iowa. And this week another Republican about to jump into the race, former Godfather's Pizza CEO and radio talk show host Herman Cain, speaks to a GOP dinner in Iowa. Rep. Ron Paul of Texas, who last week announced his candidacy for president, earlier this month was in Iowa to announce the formation of a exploratory committee. Two others who have taken steps towards running, former Minnesota Gov. Tim Pawlenty and former Sen. Rick Santorum of Pennsylvania, have each made numerous visits to the state.
Even Donald Trump is scheduled to speak in Iowa next month. The billionaire businessman, real estate mogul and reality-TV star says he'll announce by June if he's running for the GOP nomination.
According to a count by CNN, from April 1 through Sunday, probable and possible 2012 Republican presidential candidates have made 40 campaign stops in New Hampshire, which holds the first primary in the road to the White House, 39 stops in Iowa, and 20 stops in South Carolina, which holds the first southern primary in the presidential primary and caucus calendar.
–Follow Paul Steinhauser on Twitter: @psteinhausercnn