Just over one-third of voters (34%) say tonight’s vice presidential debate is Very Important to how they will vote, and over half (54%) view Joseph Biden as the more skilled debater, according to a new Rasmussen Reports national telephone survey.

For 38%, the debate is at least somewhat important to how they will vote. Only six percent (6%) say it’s not at all important.

Forty-five percent (45%) say Biden, the Democratic vice presidential nominee, is more likely to help his campaign with his debate performance, but nearly as many (43%) think his Republican challenger Sarah Palin will help her campaign more (see crosstabs).

Given the possibility of a presidential contest between the vice presidential candidates, 50% choose Biden and 40% pick Palin. An earlier survey --conducted shortly after both running mates were selected--found that Palin was preferred over Biden at that time.

The vice presidential debate in St. Louis is scheduled to begin at 9 pm Eastern, and 74% say they are Very Likely to watch. Another 16% say they are somewhat likely to view the debate, with just two percent (2%) saying they are not at all likely to watch.

Nationally Barack Obama has opened a fairly stable lead over John McCain in the Rasmussen Reports daily Presidential Tracking Poll. Underscoring the importance of the vice presidential debate, however, is the finding that 15% of voters say they still could still change their minds. Three percent (3%) remain undecided.

Last week, nearly a month after the two vice presidential candidates were announced, Palin was still viewed more favorably by voters than Biden, 54% to 49%. She also drew stronger feelings - pro and con,

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While Democratic strategists in recent days have been building up perceptions of Palin’s strength as a debater, 54% of voters see Biden as more skilled in this arena. The Democrat, 65, has been a member of the Senate for 35 years and a two-time unsuccessful candidate for his party’s presidential nomination. Palin, 44, a former city council member and mayor, is the first-term governor of Alaska.

Just 18% say Palin is a more skilled debater than Biden, but 27% are not sure.

Generally, vice presidential debates – and the candidates themselves – are regarded as relatively insignificant to the outcome of the election. But given the enthusiasm Palin has brought to GOP ranks and the harsh reaction she has drawn from Democrats, this year’s debate between the running mates has generated a great deal more interest.

(Premium Members, see Scott Rasmussen’s video commentary on tonight’s debate.)

Among the criticisms aimed at Palin is whether as a mother of five she can devote enough attention to the vice presidency given the demands of motherhood. But in a survey released Wednesday, 67% of voters said children are a motivation for women in political office, not a distraction, and nearly one-third (31%) believe being a good wife and mother is a qualification to run for higher office.

McCain’s selection of Palin as a running mate was intended in part to pick off women Democratic voters disappointed by the absence of Hillary Clinton on their party’s ticket, but women in the new poll and previous ones continue to be more critical of Palin than men.

Men, for example, in a hypothetical presidential match-up support Palin over Biden 47% to 42%. Women, by contrast, favor the Democrat 57% to 33%.

Women think Biden will help his ticket more by a 51% to 37% margin, but men give the edge on that question to Palin by virtually identical numbers.

In the Presidential race itself, Obama leads by eighteen among women but trails by five among men.

While 66% of men say tonight’s debate will be at least somewhat important to how they will vote, 77% of women feel that way. Thirty-nine percent (39%) of women say Very Important, compared to 28% of men.

Seventy-seven percent (77%) of GOP voters think Palin’s debate performance will help McCain, and 71% of Democrats feel Biden will give a boost to Obama. Undecided voters give the nod to Biden 44% to 36%s.

See survey questions and toplines. Crosstabs available for Premium Members only.