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The real reason why Democrats and their open-border allies on the left oppose a citizenship question in the census is that they have everything to lose if illegal immigrants refuse to participate.

Look at California. It is just one of several states that have more representatives in Congress and more votes in the Electoral College because of illegal immigrants — at the expense of other states.

This was a point Thomas Homan, the former Immigration and Customers Enforcement acting director, made last week on the Fox Business Channel.

“Of course, the Democrats don’t want [that] question added to the census ‘cause — because — more illegal aliens in this country and more they are counted the more electoral votes and the more power they get — more seats in the House,” he told TV host Lou Dobbs. “This is about power. This is about elections. This is about electoral votes.”

The number of illegal immigrants residing in California during the 2010 census was enough to increase its number of congressional seats and votes in the Electoral College by at least five. Who knows what that number will be just for California after the next census in 2020. (The first presidential election under the new political math would be 2024.)

It’s also no coincidence that Illinois and New York became destination states for illegal immigrants at the same time their population was dropping due to legal residents fleeing to states with lower taxes, better jobs and safer communities. As Homan said, these deeply blue states look at illegal immigrants and see a way to maintain their political power. Remember, the apportionment of seats in the House of Representatives and the number of Electoral College votes are derived from the number of heads counted by the census.

The only real solution is the National Popular Vote Interstate Compact. The compact, which is completely different from what national Democrats talk about and does not abolish the Electoral College, would negate the impact of illegal immigrants in California and other sanctuary states. Enacted by 16 states and pending in others, it will take effect when states possessing a majority of the electoral votes necessity for electing a president — 270 out of 538 — have joined the compact.

Beyond the sanctuary states, all of which reliably vote Democrat in presidential elections, it is impossible to ignore that Republican-voting Texas, Florida and Georgia have the country’s second, third and sixth highest illegal immigrant populations, according to the Pew Research Center.

This means any amnesty or so-called “comprehensive” immigration reform that legalizes illegal immigrants could make it nearly impossible for the GOP to win the White House under the current system. Just look at how candidates for the Democratic presidential nomination pandered to illegal immigrants in the party’s first debates.

Under the National Popular Vote Interstate Compact, the Electoral College is preserved but the voting method changes from the winter-take-all method of awarding electoral votes used by 48 states and the District of Columbia to a national popular vote. Simply stated, the candidate who receives the most votes nationwide would always become president. This fully constitutional reform would do away with the built-in advantage Democrats have because only citizens can vote.

Some claim a national popular vote wouldn’t matter because California and New York would simply out-vote the rest of the country. That simply isn’t true. More Americans live in red America than the country’s 100 biggest cities, which only account for about 15 percent of the vote. However, most of these Republican, conservative or conservative-inclined voters have no reason to cast a vote because the winner-take-all method used by most states doesn’t require the GOP to mobilize voters outside of the 12 battleground states. Even New York wouldn’t be as strongly Democratic as it is now since something like 1 million conservatives stay home and sit on the sidelines of presidential elections as their votes simply don’t matter under the current method.

Against these facts it is clear that conservatives and Republicans would actually benefit from the compact.

Unfortunately, some on the right are on a scare campaign to intimidate state legislators from voting for the compact. They don't understand that by switching to a popular vote, Republicans will have a better chance of winning presidential elections. Republicans will switch their strategy to focus on the red areas where people currently don't bother voting since they're not located in one of the 12 swing states.

The demographics in the swing states are changing. They're becoming more Democratic and the numbers of illegal immigrants are increasing. If we keep going with the current system, Republicans will eventually be unable to win the presidency. The National Popular Vote Interstate Compact is an idea whose time has come.