

Editor's note: Kathleen Dolan is a professor of political science at the University of Wisconsin, Milwaukee. She is the author of "Voting for Women: How the Public Evaluates Women Candidates" (Westview Press 2004). Jennifer L. Lawless is an associate professor of government and director of the Women & Politics Institute at American University. She is the author of "Becoming a Candidate: Political Ambition and the Decision to Run for Office" (Cambridge University Press 2012).
(CNN) -- Now that Mitt Romney has all but wrapped up the Republican nomination for president, the discussion has veered toward potential running mates. Who embodies the conservative credentials Romney is seen as lacking? Who can deliver a battleground state that will put Romney over the top? Who can generate the enthusiasm that will bring not only Republicans, but also independents, to the polls on Election Day?
Presidential candidates -- Democrats and Republicans alike -- have always considered factors like these. What is notable about this year's early speculation, however, is the manner in which women have been incorporated into the conversation.
We seem to have reached the point at which a woman is always included in a "veepstakes" list. The Washington Post named nine men and Gov. Susana Martinez of New Mexico as its top 10 picks. The Fiscal Times included Gov. Nikki Haley of South Carolina as one of its top seven names. And Fox News offered nine men and two women as plausible running mates.
A few days ago, on ABC, Jonathan Karl laid out several categories of contenders. His "top tier" included Sens. Marco Rubio of Florida and Rob Portman of Ohio, along with former Florida Gov. Jeb Bush. Among the "second tier" possibilities were New Jersey Gov. Chris Christie, Rep. Paul Ryan of Wisconsin, and Indiana Gov. Mitch Daniels.
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And then there were "the women." In a category all to themselves, Karl placed Sen. Kelly Ayotte of New Hampshire, as well as three governors: Haley, Martinez and Mary Fallin of Oklahoma.
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Anyone can debate the pros and cons that each of these candidates would bring to the Republican ticket. What is not up for debate, however, is that Karl, and undoubtedly many others, consider certain potential candidates as women first and political professionals second.
Before her election as governor in 2010, Fallin served two terms in the House of Representatives and 12 years as lieutenant governor. Her executive experience, therefore, is not very different from that of Daniels.
Before winning a gubernatorial election two years ago, Martinez served as district attorney (a position to which she was first elected in 1996). Her political pedigree is similar to Christie's; he served as a federal prosecutor for six years before his election as governor in 2010.
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Ayotte was New Hampshire's attorney general when she was elected to the Senate last cycle. Rubio, who joined Ayotte as a member of the freshman class, had never before held statewide office, although he had served in the Florida legislature for 10 years.
We do not mean to diminish the credentials of any of these men. In fact, that's our point. All of these names are credible and viable vice-presidential candidates. Karl doesn't say whether the women he lists are "top tier," "second tier" or even "wild cards" (another of his categories). They're just "women." Consumers of political news are denied a real analysis of these women's place in the informal pecking order.
Of course, Karl is not the first to evaluate politicians as women first and politicians second. As scholars of gender politics, we are long familiar with the tendency among the media and those who practice politics to refer to a "woman governor" or "women candidates." We hear talk about the gender gap and the Republican Party's "woman problem" as if women are one large, undifferentiated group best identified by their sex.
And we routinely see pundits, pollsters, and politicians refer to women running for office as "outsiders" (even when they're insiders) or "out-of-the-box choices" (even when they're quite conventional). This is, of course, because women are still woefully underrepresented at every level of American government. As long as women remain an anomaly in politics, their sex will continue to cause them to stand out.
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The opinions expressed in this commentary are solely those of Kathleen Dolan and Jennifer L. Lawless.