Does the country really need two Republican responses to President Obama's State of the Union address? That's what voters may be wondering on Tuesday night, when Obama's speech is followed by an official GOP response from Sen. Marco Rubio of Florida and a Tea Party rebuttal from Sen. Rand Paul of Kentucky. You can practically hear the sound of establishment Republicans tearing their hair out, with Paul's unwelcome contribution only underscoring the party's deep divisions on a night when the GOP needs to present a unified, coherent alternative to Obama.

Paul, for his part, insists that his response is not meant to upstage Rubio's. "To me, I see it as an extra response, I don't see it as necessarily divisive," Paul told CNN. "He and I don't always agree, but the thing is, this isn't about he and I, this is about the Tea Party, which is a grassroots movement, a real movement."

Still, Paul's "extra response" will likely contribute to a jarring sense of double vision for voters, as two of the GOP's best-known politicians vie to speak for the country's conservatives. As Steve Benen writes at The Maddow Blog:

What GOP officials want tomorrow night is two competing messages: The president's vision vs. the Republican vision… But there won't be two competing messages: Rand Paul guarantees there will be three. [MSNBC]

Furthermore, both Paul and Rubio are considered top potential contenders for the 2016 Republican presidential nomination, which will only feed a sense that the two men are competing against one another. "Who can talk back at Obama better?" asks Dan Hirschhorn at New York Daily News. "Call it the first showdown of the Republican 2016 presidential primaries — though the Tea Party Express doesn't see it that way."

The tag-team approach to the State of the Union has become something of a tradition for the Republican Party. Rep. Michele Bachmann (Minn.) offered a Tea Party response in 2011, while pizza magnate Herman Cain did the honors in 2012.

But party leaders must be especially frustrated this year, given that Rubio is also a Tea Party favorite, boasting that often elusive mix of bedrock base support and establishment favor. If he can't unite the party, who can?