At around 2:45 pm Tuesday afternoon, Texas Sen. Ted Cruz began speaking on the floor about his opposition to President Obama's health care law and pledged to continue to do so until he could speak no longer.

Cruz's goal isn't stopping the passage of legislation that would keep the government funded beyond Sept. 30 while stripping out the House-passed provision that would also defund Obamacare. Cruz knows that, no matter what he says or for how long he says it, the votes will proceed in the Senate into the weekend.

So, what is Cruz's goal then? To make sure that every single conservative Republican in the country knows that on the single issue that animates and unites them most, he's their guy. That he's listening to them when no one else would. (That "we need to make D.C. listen," was the single most common refrain of Cruz's speech was not an accident.)

Ted Cruz isn't popular among his Republican colleagues in the Senate or the House. He doesn't care. Ted Cruz isn't going to be the Senate majority (or minority) leader. He doesn't care. Ted Cruz isn't going to be the GOP's establishment pick for just about any office. He doesn't care.

What Cruz does care about is that among the Republican base he is known as a populist outsider who cares about them and not the ways of Washington. That he, alone among his colleagues, is willing to put principle first and do everything he can to oppose Obamacare. That, after months of asking for a piece of legislation that would defund Obamacare, Cruz is walking the walk in his opposition to the law.

Why? Because Ted Cruz isn't interested in spending years and decades climbing the Senate ladder. He doesn't want to become a lion of the Senate.

What Cruz is interested in is becoming a national figure in the Republican party and, yes, if the dominos fall right, to run for president in 2016. And, to do that, being the guy John McCain referred to as a "wacko bird" or the guy House Speaker John Boehner not-so-subtly called out over the defund Obamacare effort is a very, very good thing.

Cruz's speech --  he's been going for roughly two and a half hours as of this writing -- has repeatedly driven that point home. Time and again he noted that the Senate chamber is empty aside from him, that no one -- in either party -- is willing to stand on principle against this law. He riffed on those -- in both parties -- who have criticized his approach to the issue. He condemned Washington for its obsession with the political game and its blindness toward the concerns of real Americans. He has touted himself as the light-shiner on all of this, a force of transparency exposing the underbelly of Washington.

Just in case you have missed the last few years in Republican politics, that above paragraph is a damn good message to take to a GOP electorate in Iowa, New Hampshire or South Carolina. Ted Cruz knows that, intimately well. That's what he wants out of this speech -- and it's what he is almost certain to get.

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