PRINCETON, NJ -- Four in 10 Americans rate Mitt Romney's selection of Rep. Paul Ryan to be his running mate as either "excellent" or "pretty good," while 42% call the choice "only fair" or "poor." This even division is among the least positive reactions to a vice presidential choice Gallup has recorded in recent elections. Only George H.W. Bush's selection of Dan Quayle in 1988 generated a higher negative response, although it also generated higher positives.

The results are based on a USA Today/Gallup poll conducted Aug. 12 with 1,006 national adults.

Despite Americans' muted reaction to Ryan in general, the Wisconsin representative and Republican House Budget Committee chairman may be relatively effective at firing up the GOP base this fall, as 39% of Republicans at this point consider him an "excellent" choice. That compares with 34% of Republicans calling Sarah Palin an excellent choice in August 2008 and 18% rating Dick Cheney excellent in July 2000.

On the Democratic side, fewer than 30% of Democrats rated Joe Biden this well in August 2008 (28%) or Joe Lieberman in August 2000 (23%). Only John Edwards in July 2004 elicited more excitement from members of his own party, with 45% calling him an excellent choice.

Ryan Has Weakest Favorables, Not Widely Known

By 25% to 17%, more Americans have a favorable than unfavorable opinion of Ryan. However, nearly six in 10 are not familiar enough with Ryan to offer an opinion of him.

Nearly half of Republicans can't rate Ryan; however, those who can are mostly positive, with 50% viewing him favorably and 3% unfavorably. Democrats view Ryan more negatively, although barely a third have an unfavorable view of him (34%), while 6% have a favorable view. Independents' views are closely split, similar to the national average.

Although Ryan is not widely known, his favorable-to-unfavorable ratio is on the low side for recent vice presidential picks. For example, Palin's favorable rating among registered voters was three times greater than her unfavorable rating at the time she made her debut as John McCain's running mate at the 2008 Republican National Convention, 22% vs. 7%.

A similar contrast is seen between Ryan's current ratings and those of Edwards in 2004, as well as Lieberman and Cheney in 2000, Jack Kemp in 1996, and Al Gore in 1992. All of these candidates were viewed much more favorably than favorably -- by a 3-to-1 margin or better -- at the time they were tapped to be their party's vice presidential nominee. Reaction to Biden in 2008 was about 2-to-1 positive.

Most Voters Say Ryan Won't Affect Their Vote in November

Ryan's direct impact on the ticket is only slightly positive, with 17% of Americans saying his selection makes them more likely to support Romney and 12% less likely to support him, while 66% say it will not affect their vote.

Americans' statement that the vice presidential pick won't affect them is not unusual. In every election from 1988 through 2008, the majority of voters said each new vice-presidential nominee would not have much effect on their vote, including sizable majorities of voters in several of these.

Nearly Half Consider Ryan Qualified

Nearly half of Americans, 48%, consider Ryan qualified for the job of president, while 29% disagree and 23% are unsure. This positions Ryan ahead of both Palin and Quayle in the "qualified" rankings of past vice presidential nominees; however, he still trails all other recent candidates on this score.

Bottom Line

Vice presidential picks typically enjoy a lopsidedly positive reaction from Americans when they are first tapped to be on a presidential ticket. However, that doesn't apply to Ryan, likely owing to his leading role in authoring major conservative alternatives to President Obama's policies on healthcare and the federal budget -- plans that elicited significant Democratic criticism and pushback.

Still, Ryan appears to have two important things working in his favor at this point: 1) relatively strong support from Republicans, with about four in 10 evidently excited about him as an "excellent" choice for vice president; and 2) relatively low name ID nationally. This gives the Romney campaign a valuable opportunity to introduce Ryan to voters as his visibility skyrockets. Of course, this advantage could also become a disadvantage if the Obama campaign is able to define Ryan first in less flattering terms.

It is often noted that Americans vote for president, not vice president, so it is unclear how much views of Ryan will matter come Nov. 6. George H.W. Bush won handily in 1988 despite voters' significant doubts about Quayle; and John Kerry and Bob Dole both lost despite the initially warm public reactions to their respective running mates, Edwards and Kemp.

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