Sen. Angus King is Maine’s first independent senator.

“I work with my colleagues from both sides of the aisle,” he writes on his Senate website, “to see how we can best work together to create a better Maine and a better country for generations to come.”

This declaration is no doubt sincere, and more people with a reasonable, civil, and partnering attitude would be most welcome on Capitol Hill.

Yet Sen. King, despite his expressions of non-partisanship, votes with the Democratic side of the aisle almost uniformly. National Journal, in an article titled, “ Independent in Name Only,” observed earlier this year that King “has voted with the Democratic leadership about 90 percent of the time, the same rate of allegiance as the former chairman of the Democratic Party, fellow freshman Sen. Tim Kaine of Virginia.”

I don’t mean to indict Sen. King as some hypocritical figure; I don’t think he is. Rather, the larger point is that “independent” voting is, in practical terms, largely impossible.

Politics is about the public expression of various points of view and the enactment of those views into law. Increasingly, American politics is divided along conservative and liberal lines. The overlap of commonality between the GOP and the Democratic Party is increasingly small. Thus, as Republicans identify, substantially, as conservatives, and Democrats as liberals or progressives, anyone involved in electoral politics has to be, by virtual if not legal definition, a partisan.

The same tendencies extend to America’s electorate. According to a National Public Radio story last year, “Research over the years suggests that most independents are what John Petrocik, a political science professor at the University of Missouri-Columbia, calls ‘closet partisans.’”

Consider last year’s presidential election. As reported by U.S. News and World Report, while President Barack Obama won re-election by taking a majority of swing states, exit polling data show Obama lost the independent vote in most of those states. “Independents, who do not align with one political party or another,” the publication reported, “make up a fast-growing and coveted voting bloc.”

Think about that last sentence. Perhaps independents don’t “align” with one party or another, but they vote that way. To paraphrase Bob Dylan, ya gotta vote for somebody, and few people are as incoherent or whimsical as to vote evenly for politicians among whom there are fundamental disagreements over essential matters.

That’s why it’s important to recognize that no one ever votes strictly for an individual. When a person is elected, he becomes a partner in either one party’s “firm” or another’s – its Get out the Vote operation, its majority (or potential majority) status on the city council or in the state legislature, its fundraising arm. And on Capitol Hill, the first vote any newly elected member will cast is for either Speaker of the House or Senate Majority and Minority leaders.

So, saying, “I vote for the individual, not the party,” is either consciously disingenuous or embarrassingly naïve.

Of course, if there are two candidates running for an office and you find yourself in much greater sympathy with one than the other, your conscience should dictate how you vote even if the candidate you choose belongs to the party with which you traditionally disagree. But these instances, in a culture whose philosophical division is only accelerating, are more and more rare.

The founders of our country warned against partisanship, or what James Madison called “the violence of faction.” In “Federalist Ten,” James Madison asserted that factions would form due largely to the perceived economic self-interest of various groups.

That might have been true in the 1780s, but it is no longer. Some of the wealthiest Americans vote most consistently liberal, and many lower-middle income voters support the Republican Party because of its social conservatism.

In our time, the divide goes not so much between the wealthy and the poor as between those with one vision of American life and those with another. Deeply held convictions about the role of government, the morality of culture, and the nature of the family cut across economic lines.

No man is an island, and no voter is his own party. True partisan independence is exercised only by those so consciously inconsistent that they are uninterested in having their votes actually matter.

Angus King has every right to try to pursue an independent course in the U.S. Senate. The reality is that although his tone might be less dogmatic than that of a declared partisan, neither his voting record, nor any such record by any decision-making politician, can be.

Rob Schwarzwalder is senior vice president at the Family Research Council in Washington, D.C.