John McCain is about to name his running mate, and, of the three names most commonly heard, former Massachusetts Governor Mitt Romney is by far the candidate most preferred by voters, according to a new Rasmussen Reports national telephone survey.

Forty-seven percent (47%) have at least a somewhat favorable opinion of Romney, including 24% who say their view of him is Very Favorable. But Romney’s negatives are nearly as high, with 41% viewing him at least somewhat unfavorably including 25% who say their view of the one-time McCain rival is Very Unfavorable.

Romney is the most popular among Republican voters, with 79% giving him at least a somewhat favorable rating, including 53% Very Favorable. Thirty-five percent (35% 0f unaffiliated voters rate Romney at least somewhat favorably, with 12% Very Favorable. He also led the pack last time we ask voters who McCain should pick.

Among all voters, the two other top GOP contenders – Minnesota Governor Tim Pawlenty and Alaska Governor Sarah Palin – have less than half the support registered by Romney – and ranked sixth and ninth respectively with voters on a list of nine possible candidates.

However, the fact that 55% of voters don’t know enough about Pawlenty to comment and 67% say the same of Palin helps to explain in part the low favorability numbers.

Perhaps not surprisingly the more conservative voters felt the candidate was the higher his or her support, something for McCain to ponder as he also reportedly considers some pro-life running mates. Romney, for example, is considered conservative by 65% of voters; Palin is viewed that way by only 17%.

Twenty-one percent (21%) of voters have at least a somewhat favorable view of Pawlenty, including five percent (5%) Very Favorable. But twice as many (10%) say they have a Very Unfavorable opinion of the Minnesotan. Thirty-one percent (31%) of GOP voters and 19% of unaffiliated voters have at least a somewhat favorable view of Pawlenty.

As for Palin, 14% of all voters view her somewhat favorably but just four percent (4%) say Very Favorable. By contrast, seven percent (7%) regard the Alaskan in a very unfavorable light. While 19% of Repulicans see her at least somewhat favorably, a miniscule seven percent (7%) of unaffiliateds also feel that way.

The candidate who does best among voters is reportedly not even being considered by the Republican presidential candidate as a running mate. Former Arkansas Governor Mike Huckabee, who was McCain’s closest challenger during primary season, is viewed at least somewhat favorably by over half of voters (55%), including 21% who say they see him in a Very Favorable light. Thirty-three percent (33%) have at least a somewhat unfavorable opinion of Huckabee, 17% of whom say their view is Very Unfavorable.

Seventy-two percent (72%) of Republicans characterize their view of Huckabee as at least somewhat favorable, including 35% who say Very Favorable. Fifty-seven percent of unaffiliated voters have a favorable opinion of him, 20% Very Favorable.

In the Rasmussen Reports vice presidential markets at the time of this survey, Romney is far ahead with 80% support, followed next by Palin favored by 60%. Former Hewlett-Packard executive Carly Fiorina is next at four percent (4%), with Pawlenty at three percent (3%). Since Huckabee has never been mentioned as a serious contender for the job, only 0.6% bank on his being the vice presidential nominee. These figures are from a prediction market, not a poll and are updated on a 24/7 basis. Current expectations for leading candidates is available HERE.

Several other Republicans fare better with voters than Pawlenty and Palin.

Texas Senator Kay Bailey Hutchison is viewed at least somewhat favorably by 33% of voters and 41% of Republicans.

Flordia Governor Charlie Crist gets at least somewhat favorable marks from 26% -- and from 37% of GOP voters.

Fiorina, a longtime business executive and close advisor to McCain on economic issues, is regarded at leasts omewhat favorably by 19% of voters – and 22% of Republicans.

Two other men not even in consideration now, Bobby Jindal, the new governor of Louisiana, and Michael Steele, the former lieutenant governor of Maryland, both rate about as well with voters overall, and Republicans specifically, as the others.

Crosstabs for ideology and favorable ratings for Republican VP contenders available for Premium Members only.