DeMint is now renting a Capitol Hill townhouse for his political operation — just a few blocks from the National Republican Senatorial Committee, the official campaign arm for Senate Republicans. And unlike the NRSC, which plans to stay out of contested primaries, DeMint is prepared to be an active force, jumping into intraparty battles by pushing conservative candidates against moderate Republicans.

The buildup is the latest sign that DeMint has become the pre-eminent conservative political activist in the Senate, and he plans to push candidates whose ideological views align with his and the tea party movement’s — even if it sets up a major clash with the NRSC, which always looks for the most electable prospect…

DeMint told POLITICO his fundraising goal is a “big hill to climb, but that’s what we’re going to try to do.” And he said he wants to play a “complementary role” to the NRSC and avoid the kind of internal clashes that played out last election cycle.

But his move to a Capitol Hill townhouse is also an acknowledgment that his PAC — which launched in mid-2008 — has grown so rapidly that DeMint now needs to take extra precautions to wall off his political operations from his legislative office. Now his former legislative director, Matt Hoskins, is working full ime for the Senate Conservatives Fund after working in a dual legislative and political role last cycle.