Just 18% of voters believe that John McCain should reach across party lines and select Connecticut Senator Joe Lieberman as his Vice-Presidential running mate. The latest Rasmussen Reports national telephone survey found that 42% say he should not offer the job to Lieberman while 40% are not sure.

The concept of a McCain-Lieberman ticket is supported by 19% of Republicans, 14% of Democrats, and 22% of voters not affiliated with either major party.

Lieberman has considered himself an Independent Democrat ever since he lost the Democratic Primary during his re-election bid two years ago. He then ran—and won—as an Independent. He still caucuses with the Democrats in the Senate, a fact that gives the Democrats their current status as majority party. However, he has endorsed McCain for President and angered many Democrats with his visible support for the GOP’s presumptive nominee. Some pundits have suggested that adding Lieberman to the ticket would be a bold move to highlight McCain’s ability to work across traditional party lines.

The poll also found that an Obama-Clinton ticket would narrowly defeat a McCain-Lieberman ticket, 46% to 44%. Perhaps the most striking feature of that result is that it is so similar to the results for an Obama-McCain match-up without mentioning Vice-Presidential picks. At the time this poll was taken, Obama held a very slight edge over McCain in the Rasmussen Reports daily Presidential Tracking Poll. This suggests that either Clinton and Lieberman either have no impact at all or cancel each other out.

Just 47% of all voters say it’s important for McCain to pick someone younger as his running mate. Thirty-nine percent (39%) say it’s Not Very Important and 9% believe it is Not at All important.

Thirteen percent (13%) believe McCain should pick a woman or a minority candidate to be his running mate. Forty-seven percent (47%) disagree and 40% are not sure. Seventeen percent (17%) of Democrats say McCain should pick a woman or minority candidate. Fifteen percent (15%) of unaffiliated voters agree along with 6% of Republicans.

Overall, as they consider their options for November, 36% of voters say a Vice Presidential candidate is a very important factor in making their decision. That figure includes 48% of Democrats, 30% of Republicans, and 25% of unaffiliated voters.

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