Sen. Marco Rubio, seen May 20, 2015 in Washington, officially launched his presidential campaign in April. (Win Mcnamee/Getty Images)

It isn’t often that a presidential campaign blueprint comes packaged between covers and available in bookstores and online for all to see. But that’s the inescapable conclusion from looking through the pages of the book entitled, “2016 and Beyond,” by Republican pollster Whit Ayres.

Ayres is one of his party’s leading analysts. He also happens to be the pollster for Sen. Marco Rubio (R-Fla.). The new book is subtitled, “How Republicans Can Elect a President in the New America.” If not exactly the strategy memo for a Rubio campaign, it’s a good proxy.

Ayres’s demographic analysis looks at the issue of a changing United States from the perspective of the growing minority population (and his party’s weaknesses there) and the majority white population (and his party’s strengths and limitations there). His argument is straightforward: To win the White House, Republicans must systematically improve their performance among minorities while maintaining or even improving their support among white voters.

In an electorate in which the white share of the vote was 72 percent, President Obama won reelection in 2012 despite losing the white vote by a bigger margin than any winning Democrat in the past. The white share of the electorate in 2016 will be a point or two smaller.

Based on estimates of the composition of the 2016 electorate, if the next GOP nominee wins the same share of the white vote as Mitt Romney won in 2012 (59 percent), he or she would need to win 30 percent of the nonwhite vote. Set against recent history, that is a daunting obstacle. Romney won only 17 percent of nonwhite voters in 2012. John McCain won 19 percent in 2008. George W. Bush won 26 percent in 2004.

Sen. Marco Rubio, who's running for president in 2016, is known for his stances on immigration and tax reform. Here's the Florida Republican's take on Obamacare, the Islamic State and more, in his own words. (Julie Percha/The Washington Post)

Put another way, if the 2016 nominee gets no better than Romney’s 17 percent of the nonwhite vote, he or she would need 65 percent of the white vote to win, a level achieved in modern times only by Ronald Reagan in his 1984 landslide. Bush’s 2004 winning formula — 26 percent of the nonwhite vote and 58 percent of the white vote — would be a losing formula in 2016, given population changes.

Ayres also points out that the GOP’s support among whites is not evenly distributed across the country. He notes that Romney won “overwhelming margins” among whites in conservative Southern states, but won fewer than half the white vote in Northern states such as Maine, Vermont, Iowa, New Hampshire and Oregon. More importantly, Romney won fewer white votes than he needed in Ohio, Michigan, Pennsylvania, Wisconsin and Minnesota.

To Ayres, this isn’t an either-or choice for the GOP. As he puts it, “For Republicans to become competitive again in presidential elections, Republican candidates must perform better among whites, especially in the overwhelmingly white states of the upper Midwest, and much better among minorities.”

The coming Republican nomination contest will test the appeal of the candidates with both groups of voters. Is there any candidate who can raise the share of the nonwhite vote and attract more white votes in the Midwest?

When I put that question to Ayres, he said yes but only “if that candidate can relate to people who are struggling economically and relate to people who have been disadvantaged by a remarkably changing economy.”

Ayres addresses immigration at length, seeking to debunk those in his party who say Hispanics will always vote overwhelmingly for Democrats or those who say there are more than enough white voters who stayed home in 2012 to make up the deficit by which Romney lost.

He lists any number of GOP candidates who have won significant portions of Hispanic voters in state races and includes an interesting table that shows that, even if all the “missing white voters” had turned out in 2012 and if Romney had won them all, “he still would have lost the election.”

Much of Ayres’s book is an examination of public opinion on a range of issues. His conclusion is that, on the key issue of the role and the size of government, the country is center-right, not center-left. On debt and deficit, he argues that a Republican candidate is on solid ground talking about both, as long as he or she doesn’t make it all about the numbers and instead links it to policies to stimulate more economic growth.

He says cultural hot buttons of abortion and same-sex marriage are separable. On abortion, he argues that Americans are and will remain “torn about the morality” of the issue and sees no particular downside for the GOP to remain the antiabortion party, as long as candidates talk about it with sensitivity.

On same-sex marriage, he concludes that the political debate is over and that public opinion has made a decisive shift. But he acknowledges that changing the party’s position will be wrenchingly difficult and sketches out some do’s and don’ts for those opposed, including not advocating federal intervention to overturn same-sex marriages adopted through referendums or legislative action.

Ayres urges Republicans to set aside their satisfaction over their big victories in 2010 and 2014 and focus on the reasons they have fallen short in the past two presidential campaigns. He reminds them that deepening their hold on state and local offices in red states is no indicator of their presidential prospects.

In one example, he looks at the dominance of the Republican Party at the state level in states that Romney won in 2012. The party holds between 53 percent and 87 percent of the state senate seats in those places, according to Ayres’s calculations. Some Republicans, he argues, look at those numbers and say, what’s the problem? But Ayres notes that those states still leave the Republicans well short of the 270 electoral votes needed to win the presidency.

Ayres said he wrote and published the book before Rubio made a final decision to run for president and said he hoped it would be a blueprint not just for Rubio but for any of the candidates running in 2016. What the party needs, he said, is a candidate who will prompt people who have not voted for the Republicans in the past to consider doing so in 2016 rather than one who offers modifications in message.

“It’s more a matter of not nominating a candidate who looks like the same old, same old, but who looks like a fresh start for the party,” he said in a phone interview Friday.

“It’s bigger than this position or that position,” he added. “Republicans have got to nominate a transformational candidate because the country has changed more than most of us realized, even in the last 12 years.”

Rubio will choose to run as he sees fit, but the similarities between what he already is saying and doing and what Ayres lays out in his book are striking. The interest in a Rubio candidacy clearly exists within the party for the reasons that Ayres outlines. But there is a large leap from the pages of a pollster’s book to the rigors of a presidential campaign.

Ayres has offered the road map. Now comes the road test of whether the candidate can deliver.