One measure of how well John McCain kept his choice of a vice presidential running mate secret is that 67% of voters nationwide have no opinion one way or the other about Alaska Governor Sarah Palin. The latest Rasmussen Reports national telephone survey shows that she is unknown to 78% of women.

In fact, among 10 leading Republicans included in the poll, Palin’s name was the least recognized.

However, in Alaska, the 44-year old Governor and hockey mom earns good or excellent ratings from 64% of voters statewide. Just 14% say she is doing a poor job. In a state whose senior Republican Senator has been indicted for ethical violations, 84% say Palin is at least as ethical as most politicians. Most (51%) say she’s more ethical than her peers (full demographic crosstabs available for Premium Members).

Palin is only the second woman to ever be on a major national political ticket after Democrat Geraldine Ferraro in 1984. Her choice is clearly aimed at peeling away disaffected female voters in the Democratic Party still smarting from Hillary Clinton’s failure to grab the nomination – and Barack Obama’s decision not to even consider her for the number two slot.

Nationwide, four percent (4%) have a Very Favorable opinion of Palin while seven percent (7%) have a Very Unfavorable view. Twenty-one percent (21%) hold less firm opinions of her and are evenly divided.

Seventeen percent (17%) nationwide view her as somewhat or very conservative and 16% view her as somewhat or very liberal. Again, the primary lesson from the data is how little known the Alaska governor is prior to today’s announcement.

The selection of Palin means that no matter who wins in November, history will be made. The nation will either have its first African-American president or its first woman vice president.

On a July 16 radio interview, Scott Rasmussen indicated that Palin would be John McCain’s strongest vice presidential pick. For the Democrats, he named Virginia Governor Tim Kaine.

Of the three names most commonly heard as being in contention for the GOP’s vice presidential slot in the hours before McCain’s announcement was known, former Massachusetts Governor Mitt Romney was by far the most popular candidate.

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

Romney was the most popular among Republican voters, with 79% giving him at least a somewhat favorable rating, including 53% Very Favorable. Thirty-five percent (35%) of unaffiliated voters rated Romney at least somewhat favorably, with 12% Very Favorable.