* Romney to formally announce next week
* Favorite to win in New Hampshire primary
By Nick Carey
DES MOINES, Iowa, May 27 (Reuters) - Republican presidential hopeful Mitt Romney on Friday made his first visit of this year to Iowa to test the waters in a key state he lost to a more conservative rival in his failed 2008 election bid.
The former Massachusetts governor, who will formally announce next week that he is in the race for his party's nomination in 2012, tops many national polls among Republican candidates and has a solid fund-raising operation that raised $10 million in a single day last week.
But in Iowa, which kicks off the Republican presidential primary season in February 2012, Romney may have a steep hill to climb.
Republican caucuses in this Midwestern farming state have increasingly come to favor social conservatives, while Romney is more to the center of the party.
Nationally, multimillionaire Romney heads most opinion polls of likely Republican candidates, but polls show him lagging in a face-off with Democratic President Barack Obama.
Obama was the main target of the former governor's speech on Friday, as Romney contrasted his own background in the private sector and understanding of the economy with what he described as Obama's lack of experience.
"This president just doesn't get what it takes to once again make this a highly successful, robust economy," he said. "We're going to change that."
Romney is favorite to win the primary vote in the other main early voting state of New Hampshire, which is next door to Massachusetts and not as conservative as Iowa.
But interviews with conservative Tea Party group members across Iowa -- the type of voter Republican strategists say Romney must win over -- suggest he is unpopular.
"I don't like him (Romney) one bit," said Judd Saul of the Cedar Valley Tea Party group, in east central Iowa. "He's a socialist in conservative's clothing."
In a poll of likely caucus participants conducted by the 2012 Iowa Report this week, Romney came in seventh among likely caucus voters with just 3.5 percent support.
Former Arkansas governor Mike Huckabee won the Iowa caucuses in 2008 but Arizona Senator John McCain eventually won the nomination. Huckabee has taken himself out of the race this time around.
'HOT OR COLD?'
Republican strategist Ron Bonjean said this Iowa visit is critical for Romney to assess how much effort and resources to put into the state, or whether to focus elsewhere.
"Romney is testing the waters to see how much energy he has to invest in Iowa. He wants to dip his toe in the water and ask 'is it hot or cold?' before he jumps in," Bonjean said.
"The last time around in 2008, he put a lot of money on the table here in Iowa and he lost anyway. If the hill is too steep for him to climb here then he will still campaign in Iowa, but he likely will focus more on other big races like New Hampshire, South Carolina and Florida."
A major problem Romney faces among conservatives in Iowa and elsewhere is the similarity between the healthcare reforms he oversaw as Massachusetts governor and that of Obama -- which conservatives derisively call "Romneycare" and "Obamacare." Romney did not mention his healthcare plan during his speech on Friday.
"Romney carries a lot of baggage because of Romneycare," said Gregg Cummings, a conservative from southern Iowa. "Based on what I've heard from people around the state, he doesn't have a prayer of winning in the state of Iowa." (Editing by Vicki Allen)