A specter hangs over the Democratic veepstakes: The specter of Charlie Baker. And John Kasich. And, to an extent, Chris Christie.  Reportedly, Hillary Clinton's campaign's long list for a running mate includes Sen. Elizabeth Warren (D-Mass.), Sen. Sherrod Brown (D-Ohio), and Sen. Cory Booker (D-N.J.). Each hails from a state where a Republican governor would appoint a replacement if the Democrat left to serve in a Clinton administration. The irony is especially acute for Warren, who rescued a seat lost by Martha Coakley, and who might hand control of that seat to a governor elected by defeating ... Martha Coakley.  [The Fix: In Clinton’s vice presidential search, Tim Kaine is right at the top]  Democrats are not allowing themselves to be surprised by this, and Sen. Harry M. Reid (D-Nev.) has already started to explore ways to shorten the time that Massachusetts, at least, would send a Republican to the Senate. Still, the fate of Senate seats — and the utility of several of these people serving as senators — is treated as a sidebar to the major issues of whether Clinton taps a progressive running mate or seeks out someone who could theoretically tack to the center.  This is strange, and Democrats keep doing it. Since at least 1992, when Bill Clinton tapped Al Gore as his running mate, Democrats have raided Congress to staff their administrations in ways that opened up Republican electoral opportunities.  Obviously, public servants are under no obligation to cling onto their seats for the party's maximum advantage; obviously, parties make a cost-benefit analysis when they pull people out of elective office to serve in the administration. But over the last generation, Democrats have raided their bench with more consequence than Republicans. Gore's exit from Tennessee made the state's 1994 Senate races even more attractive — and winnable — for the opposition, and Clinton's decision to pull then-Texas Sen. Lloyd Bentsen into the Cabinet created the opening for Kay Bailey Hutchison to accelerate the GOP's Texan dominance.  But in both cases, that era's Democrats controlled southern state houses and were able to replace the exiting senators. In 2000, when he sought the presidency, Gore chose then-Sen. Joe Lieberman (D-Conn.) to run with him. Had Gore won his court cases, and won Florida, Democrats would have controlled the Senate. Then Lieberman would have handed control of his Senate seat over to then-Gov. John Rowland, a Republican, flipping control back to the defeated party.  In 2004, John Kerry risked nothing by bringing John Edwards (remember him?) onto the ticket. Edwards, whose ambition nearly matched his penchant for self-destruction, gave up his Senate seat to run for president, and it went Republican as the state voted for the Bush-Cheney ticket.  But in 2008, Barack Obama risked a bit more when he tapped Joe Biden. The Delaware senator, who was up for reelection that year, easily won his Senate race the same day and empowered a Democratic governor to appoint a placeholder for two years. First, Democrats hoped that popular Republican congressman Mike Castle would sit out the 2010 race. Then, they fretted as he entered it and led in the polls. Finally, they got a lucky break as Castle went down to tea party candidate Christine O'Donnell in the primary, setting up a race won easily by now-Sen. Christopher A. Coons (D-Del.).  The luck in other states was mixed. Infamously, then-Illinois Gov. Rod Blagojevich, a member of the president's party, resigned in disgrace after seeking favors from whomever he appointed to fill Obama's senate seat. That scandal — and the additional scandals of the Democrats' 2010 nominee for the seat — helped hand the seat to now-Sen. Mark Kirk (R-Ill.), who Democrats will spend millions of dollars to (they hope) dislodge this year.  Obama also pulled then-Sen. Ken Salazar of Colorado into his Cabinet, and only an O'Donnellesque failure of judgment by Colorado Republican primary voters saved his successor, Michael F. Bennet. Arizona Democrats were not so lucky, as then-Gov. Janet Napolitano's (D) escape into the Obama Cabinet elevated Republican Jan Brewer into the governor's mansion, removing the last barrier to Republican control of legislation — making the SB1070 immigration law possible, among other things.  None of these people were yanked, kicking and screaming, from their elected offices. Some of them sought those offices with an inkling that they'd be tapped for something bigger.  That's just the problem with the veepstakes, though. If the political offices seen as preparation for the highest office were Russian matryoshka dolls, with smaller ones fitting inside larger ones, they'd go in this order: House, Senate, governor, vice president. Serving in a Cabinet, as possible veep picks Julian Castro and Thomas Perez have, is not in the order. A Senate seat is in the order, so it's assumed that a senator who excels should head to the executive branch.  This is blinkered in several ways. It minimizes the role of the Senate — what it can achieve, how important it is to control it — even after Democrats spent eight years learning how lacking 60 seats there, much less 51 seats, can stop an agenda cold. At the same time, it makes the strange assumption that being elected to the Senate and serving on a relevant committee is better preparation, more credibility-enhancing, than running one of the government's massive departments. Whoever runs a Senate office, or even a committee, has perhaps a few dozen employees. The secretary of labor — Perez's job — has 17,450 employees.  In parliamentary democracies*, there is no need to raid a legislature and give lawmakers new jobs in a cabinet. The cabinets are composed of members of Parliament; they can be reshuffled without much consequence. In our system, giving a plum job to a senator means you may be letting the opposition party make an appointment that can block your legislation. Democrats know this, which is why there's been so much study of the possible Warren pick, and why Brown is not actually likely to get the job. But the whole discussion is a symptom of our focus on the presidency as the be-all, end-all, the star in an American drama. Democrats, who are badly outnumbered in state-level offices and have adopted a habit of getting blown out in midterm years, can't go along with that so easily.  * Yes, we're a republic — don't worry, this isn't the weekend where I'd forget that.
Three top potential Clinton VPs would pave the way for a Republican governor to replace them in the Senate.