A recent conversation with a veteran of GOP presidential campaigns raised this question: Which, if any, of the recent battleground states are likely to become more Republican by 2016? The consensus: very few.

That reality highlights one problem Republicans face as they seek to regain the White House after six years under President Obama. Lots of factors affect elections: the quality of the candidates, the state of the economy, the effectiveness of the campaigns. But in a country whose demographics continue to change, Republicans will begin this campaign with one significant disadvantage.

Over the past three decades, the political leanings of many states have shifted dramatically. What once was a sizable Republican advantage in the electoral college has become a decided Democratic advantage.

One way to look at this is by comparing two overlapping 20-year periods. In the first, 1980 through 2000, Republicans won four of six presidential elections. In the second, 1992 through 2012, Democrats won four of six.

The first period was the era of Republican dominance — the start of the Reagan era. In the 1980s, many people suggested that Republicans had a lock on the electoral college. Democrats were in woeful shape. Here’s what the numbers showed:

Republicans won 16 states in each of the six elections during that period and won an additional four states in five of the six. That added up to 179 electoral votes, based on census apportionments in 2000. Today, those 20 states account for 193 electoral votes as a result of the population shift from north to south. Democrats won just one state — Minnesota — plus the District of Columbia in all six elections. They counted only two more states where they won five of six. Together, those four accounted for just 21 electoral votes.

From 1980-2000, 10 states were up for grabs, with each party winning them three times over six elections. They accounted for 155 electoral votes in 2000, and 147 today. What has happened to those once-contested states highlights the dramatic change that has taken place since, namely a shift of some major states toward the Democrats.

From 1992-2012, Democrats built a base that rivals or exceeds that of the Republicans in the earlier period. Eighteen states and the District have voted Democratic in each of the six presidential elections. They represent a total 242 electoral votes, according to the current allocation. Three other states, with a total of 15 electoral votes, have backed the Democrats five times.

Meanwhile, Republicans won 13 states in those six elections, but because most of them were smaller states, their electoral votes totaled just 102. The biggest consistent GOP state in this period has been Texas, with 38 electoral votes. Five other states backed the GOP nominee in five of the six elections, for an additional 56 electoral votes.

Adding together the states that voted Republican or Democratic in at least four of the six elections gave Democrats 281 electoral votes and Republicans 219. Only two states — Colorado and Florida, with a total of 38 electoral votes — were won three times for each party in those six elections.

What happened? States whose loyalties were divided in the first era moved to become part of the Democrats’ base — a transition that began with Bill Clinton’s two campaigns and continued through 2012. That list includes California, the biggest electoral prize in the country, with 55 votes, but also others that have long been considered contested battlegrounds, including Illinois, Michigan, New Jersey and Pennsylvania.

All 16 states that went for the GOP in the past six elections remain solidly in the Republican column. The same is true of most of the states that voted GOP in four or five of the past six. But that leaves the Republicans far short of the 270 electoral votes needed to win the White House.

Over the past six elections, Republicans have averaged just 211 electoral votes and have not won more than 286 since 1988. Democrats averaged 327 electoral votes for those six elections, and their lowest total, even in losing, was 251 in 2004. Given the current alignment, the Republicans must find states that have been voting Democratic and convert them to their column in 2016.

For perspective, I asked William H. Frey, a demographer and census expert at the Brookings Institution, as well as Republican and Democratic strategists of past campaigns, for their assessments of trends in the battleground states, based on demography and internal politics.

Frey analyzed nine states and found little good news for the Republicans. He found five — Colorado, Florida, Nevada, North Carolina and Virginia — definitely moving toward the Democrats because of their growing diversity. Obama won all but North Carolina in both of his presidential races.

Frey cited Ohio as one state that could become more hospitable to Republicans, because aging white baby boomers continue to make up a large part of the population there. Noting that candidate quality can make a difference, he wrote in an e-mail, “Democrats would have to be lucky and much more pro-active with blue collar whites to continue success there.”

He sees some glimmers of hope for Republicans in Michigan and Pennsylvania, if the GOP can find the right candidate. But he also envisions potential problems for the party in states such as Arizona and Georgia, which he said could be toss-ups by 2016 and could lean Democratic in the long run.

Frey said three states — Iowa, New Hampshire and Wisconsin — probably will continue to be toss-ups, in large part because of smaller minority populations. But none can be said to be moving in the GOP’s direction.

Republican and Democratic strategists who offered private assessments do not disagree significantly with Frey’s analysis, although all were more a little bullish about their own party’s chances.

From the GOP perspective, Florida and North Carolina may be moving in a Republican direction. But one GOP strategist said that Colorado, Nevada, New Hampshire and Virginia are actually moving toward the Democrats. Most of the other possible battlegrounds, with the exception of Georgia, appear to be politically static, which would be better news for Democrats.

Several Democratic strategists see movement toward Democrats almost everywhere, although they stop short of claiming an electoral-college lock. Democrats contend that a growing Hispanic population is pushing Florida in the party’s direction and that Georgia’s growing diversity eventually will make it a contested state. Democrats also have hopes that Arizona and Texas will become competitive for the same reason, although it is doubtful that Texas will be competitive by 2016.

Democrats recognize that Ohio will always require maximum effort and could go either way in the future, and they acknowledge that, under the right circumstances, Michigan and Pennsylvania could be more hospitable to a Republican nominee.

That will depend on how white voters divide. Obama did poorly among that group but still won those states. Would Hillary Rodham Clinton do any worse among whites, if she became the Democratic nominee?

Nothing is static in politics. Just as the Democrats’ growth in the suburbs began to change things in the mid-1990s, a Republican candidate who is significantly more successful at winning Hispanic votes than the party’s past two nominees could quickly change the calculus of some of these contested states. Obama’s standing in 2016 will shape the climate. If he is highly unpopular, that, too, would help the GOP. But Republicans have considerable ground to recapture to win the presidency, and underlying trends have not been helping them.