In picking Mike Pence, the staunchly conservative governor of Indiana, as his running mate, Donald Trump probably made a wise choice. Photograph by Aaron P. Bernstein / Getty

Over the past couple of months, Donald Trump hasn’t done much right, but in picking Mike Pence, the staunchly conservative governor of Indiana, as his running mate, he probably made a wise choice. History suggests that Vice-Presidential candidates don’t make much, if any, difference to the outcome of Presidential elections, but here are some reasons why, from Trump’s perspective, Pence was the best bet:

**1. He’s not Newt Gingrich. **The other day Rich Lowry, the editor of National Review, argued that, since Trump is running a media campaign, he might as well double down by selecting Gingrich, a fellow blowhard who can’t resist appearing on television. (No, Lowry didn’t use those exact words.) But that wouldn’t have been a smart move. The running mate’s role is to support and amplify the boss’s message, not to usurp it. As Gingrich demonstrated on Thursday night, with his call for American Muslims to be subjected to a Sharia-law test, he’s not one of nature’s number twos. (My colleague Amy Davidson has more on that story.) For Trump, indeed, about the only benefit of having the former Speaker on the ticket would have been to make his lowly approval rating—35.5 per cent, according to the Huffington Post’s poll average—look better. The last time Gallup surveyed Gingrich’s approval numbers, in 2012, he had a favorability rating of twenty-six per cent.

**2. He’s not Chris Christie. **Many of the potential problems with picking Gingrich also apply to the New Jersey governor, who is loud and domineering, and has an equally dismal approval rating: thirty-four per cent, according to Gallup. And, with the Bridgegate scandal still rumbling on, Christie is an opposition researcher’s delight. Plus, he hails from just across the Hudson River, which means he’d be a liability from a geographical perspective. As Rudy Giuliani found out in 2008, and as Christie himself discovered in this year’s primaries, many Republicans who inhabit the far-off regions of the famous Saul Steinberg drawing tend not to warm to brash products of the metropolitan area on the Presidential ticket.

**3. He’s a Midwesterner. **Further to my previous point, Trump’s only realistic, or semi-realistic, chance of getting to two hundred and seventy electoral votes is to storm through the Midwest and the Rust Belt, racking up huge majorities of white votes. To this end, his ideal choice would have been John Kasich, the popular governor of Ohio, but Kasich didn’t want the job. Nor did Rob Portman, the Ohio senator who served in the Bush Administration, or Scott Walker, the governor of Wisconsin. And no one in Michigan or Pennsylvania was particularly suitable, either. That left Pence, who runs the most staunchly Republican state in the region. Although his ardent social conservatism may turn off some people in the suburbs of Detroit and Cincinnati, he can claim to be a Midwesterner through and through.

**4. Conservatives like him. **The central fact about the modern Republican Party is that it is aggressively conservative. Trump, in some realms, has seemed eager to defy this fact, or, perhaps, to try to redefine what conservatism means. In May, after wrapping up the nomination, he said, “This is called the Republican Party, not the Conservative Party.” But, like John McCain and Mitt Romney before him, Trump ultimately had to come to terms with the nature of the beast he is trying to ride to the White House. In picking Pence, reportedly on the advice of Paul Manafort, the veteran Republican strategist he hired to run his campaign, Trump acknowledged that a G.O.P. candidate needs the consent, if not the active support, of the conservative movement.

**5. Establishment Republicans like him. **As my colleague Ryan Lizza pointed out months ago, Trump’s victory in the primaries represented a hostile takeover of the Republican Party. But, since he won the nomination, it has become patently obvious that he doesn’t have a campaign operation of his own to speak of, which means that he is depending on the Party apparatus, and especially the Republican National Committee, to raise money, organize the Convention, and put together a ground game. Selecting Pence, a former head of the Republican Study Group on Capitol Hill, sends a signal that Trump is willing to work with the Party establishment and listen to what it says. That might not help him much with Republican voters—the primaries made it clear that they don’t necessarily agree with the establishment line on many issues—but it will make it easier for Trump to mount a national campaign.

**6. Paul Ryan likes him. **These days, the forty-six-year-old Speaker of the House is the most influential establishment Republican. And, although Ryan has publicly endorsed Trump, he has done so with all the enthusiasm of a man en route to a colonoscopy. But, if he can’t yet find it in himself to say nice things about Trump, he has no such hesitation when it comes to Pence. Minutes after Trump confirmed the selection, Ryan released a statement saying that there could be “no better choice for our vice-presidential candidate.” The Speaker will now be anticipating next week’s Convention, which he is chairing, with less trepidation. And, since Trump desperately needs a show of unity next week, and a show of support from Ryan, that matters quite a bit.

**7. There may not be many liberal and moderate voters left for Trump to alienate. **On Friday, the Clinton campaign seized on Pence’s reactionary stances on issues like abortion, gay rights, immigration, and the minimum wage, describing him in a statement as “the most extreme pick in a generation.” Although some who recall John McCain’s selection of Sarah Palin might dispute that description, Pence is clearly very conservative, especially on social issues. However, it’s far from clear that adding his social conservatism to the toxic brew that Trump has already concocted will cost the ticket very many votes. Most people who take civil rights and the Constitution seriously are already aghast at the prospect of a Trump Presidency. Is there anyone out there who was willing to look past Trump’s call for a ban on Muslims, a resumption of torture, and the deportation of eleven million undocumented workers, but who will not vote for the Republican ticket because of Pence’s support for an Indiana law that allowed businesses to discriminate against gays and lesbians? Perhaps such people exist, but I doubt there are very many.