Could It be Trump-Sessions? Clinton-Kaine?

Ted Cruz got at least one thing right in naming Carly Fiorina as his running mate in his futile bid to win the Republican nomination: the proper attributes for a vice presidential candidate.

Hillary Clinton and Donald Trump could do worse than to base their choices on the Cruz parameters for prospective running mates: knowledge and experience, judgment and character.

Vice presidential choices are always important; one out of three has become president, including four of the last nine. But the choice has become more important in an age in which candidates must pass intensive media scrutiny and perform before millions in a single vice presidential debate. An added factor this year is that Trump will be 70 next month, and Clinton 69 in October.

Since Jimmy Carter made Walter Mondale the first significant vice presidential partner, most nominees have wisely picked someone qualified to play a significant governmental role, rather than serve primarily as political attack dog, ticket balancer or traveling envoy. That could be especially important for Trump, given his lack of governmental experience.

Trump’s unpredictability makes assessing possible GOP choices hard. But it would seem sensible for him to pick someone with the Washington experience he lacks, like Mitt Romney selected Rep. Paul Ryan and George W. Bush picked Dick Cheney.

His top Washington ally has been Sen. Jeff Sessions of Alabama, a former federal judge. A small group of GOP lawmakers that met in March with Trump included another prospect, Sen. Tom Cotton, an ambitious young Arkansan and Iraq War veteran.

Another possibility is a former GOP foe like New Jersey Gov. Chris Christie, who enthusiastically endorsed him and could complement his blue-collar appeal. But the blunt Christie may be too similar to Trump and, besides, has very low approval ratings in his home state. Another Trump endorser, Ben Carson, is popular with GOP conservatives but also has no governmental experience.

On paper, Sen. Marco Rubio of Florida seems a natural fit. Though Trump denigrated him as “little Marco” and lured him into the political gutter, the young Cuban-American senator and former state legislator would provide generational, ethnic, geographic and experience balance.

Thanks to Tuesday’s victory in Indiana, Trump won’t need to make a deal to reach the required 1,237 delegates. And his repeated denunciations of Cruz as “lying Ted” and their continuing enmity make the Texas senator an unlikely vice presidential choice. That leaves Ohio Gov. John Kasich, who would bring both state and federal experience, though he has adamantly rejected the idea. He wouldn’t be the first to change his mind.

Three women who have been suggested, if Trump wants to counter likely rival Clinton, are Sen. Joni Ernst of Iowa, Gov. Nikki Haley of South Carolina and Gov. Susanna Martinez of New Mexico. All three backed Rubio, and Haley was particularly critical of Trump.

Agreeing to be Trump’s vice president might involve a gigantic leap of faith, both in terms of what life would be like and politically. History says being on a losing ticket doesn’t benefit future ambitions.

As for Clinton, the Democratic front-runner’s campaign did something unusual recently in providing a list of people under consideration that looked very much like a real list, not one leaked for political purposes.

Two names stood out, by virtue of experience and background: Sens. Tim Kaine of Virginia and Sherrod Brown of Ohio. Kaine, a former mayor and governor, is a Spanish-speaking Roman Catholic designated to speak for Clinton on foreign policy issues. Brown is a populist with positions similar to those of Bernie Sanders, like requiring banks to downsize. Both have won several state-wide elections in major swing states.

The other three were former Gov. Deval Patrick of Massachusetts, an African-American who was assistant attorney general under Bill Clinton; Virginia’s other senator, Mark Warner, also a former governor; and Tom Perez, the secretary of labor. Another Hispanic sometimes mentioned is Julian Castro, the secretary of housing and urban development and former San Antonio mayor. So is Massachusetts Sen. Elizabeth Warren.

But given how Trump has disparaged minorities and women, the likely first major party female nominee might prefer a qualified white male like Kaine or Brown, rather than a minority or a woman.

As for Fiorina, her tenure as a vice presidential candidate was one of the shortest in history, though she showed she definitely fit two traditional vice presidential roles, political soul mate and attack dog.