Indiana Republicans go to the polls tomorrow to decide whether to re-nominate 80-year-old 36-year Senate veteran Richard Lugar or to pick instead State Treasurer Richard Mourdock, running as the conservative alternative. In the usual course of events, my advice for activists and pundits alike in these races is to not forget that every race is unique, based on the individual candidates, the state or district, and the issue environment of the day. Not every state is Utah or Rhode Island; not every conservative is Marco Rubio or Christine O’Donnell; not every moderate is Chris Christie or Jim Jeffords. Often (but not always), the better candidate wins, whether or not that candidate is the most conservative, the most Establishment-backed, or considered the most ‘electable’ by pundits and political pros.

That being said, the conditions of 2012 – specifically, the now-certain nomination of Mitt Romney as the Republican candidate for president – call for conservatives to take a harder line than ever in supporting Operation Counterweight (William Jacobson’s term), in particular to seek in Senate races what David Freddoso has called “an un-bossable Senate.” Party insiders expect conservatives, Tea Party-style outsiders and single-issue social conservatives to show up to vote anyway for a party whose leader is a man many of us distrust on nearly every issue. Politics, they remind us, is compromise. And that’s precisely my point: it is exactly because one side of the party got Romney that the other can less afford to swallow Romney-like figures in the Senate. That doesn’t mean backing the most conservative candidate in every single race without considering any other factor – but it does mean giving more than usual preference to the more conservative and/or less establishment option in Senate races. It’s not about demanding absolute party purity – it’s about recognizing that Romney has sopped up most of our tolerance for impurity already. If you want a Senate that will hold Romney’s feet to the fire, you have to start by replacing men like Dick Lugar and, in Utah, 78-year old Orrin Hatch.

Republican voters have a tremendous opportunity to write on a clean slate in 2012’s Senate races. Out of 33 Senate races, only 7 feature a Republican incumbent, and only three of those have been in office for a full term: Bob Corker of Tennessee (running for his second term, having been first elected in 2006), Lugar, and Hatch, who like Lugar was first elected in 1976 on the coattails of Gerald Ford (who carried both their states that year against Jimmy Carter).

Considered solely from the vantage point of partisan loyalty, you might regard Lugar as a good Republican, and Hatch an excellent one. And indeed, Lugar came to Washington in the 70s as very much a mainstream Republican, not significantly less conservative within the context of his times than Mourdock, and Hatch arrived as a movement conservative, much like his current opponent, State Senator Dan Liljenquist. But 36 years in the Senate will make all but the hardiest souls go native. Indeed, in Hatch’s case that was his campaign theme in 1976, running against three-term Democratic incumbent Frank Moss: “What do you call a Senator who’s served in office for 18 years?” “You call him home.” Even if you think these men have done more good than harm in the Senate, it is time to replace them with younger, better alternatives.

As I’ve noted before, besides the various ideological and cultural divides within the GOP, a core dividing line is over a sense of urgency to contain the runaway growth of federal spending and the reach of the federal government. It is difficult to picture Lugar and Hatch, as a pair of courtly octogenarians, having the necessary energy not only to seek what is apt to be a difficult partisan confrontation over these issues, but to put pressure on a president from their own party. And while Utah voters will surely be excited to go to the polls for Romney, conservative voters in other states like Indiana will need more encouragement – not yet another message that the establishment has shut them out. That’s good news in Ohio, where a fresh face (State Treasurer Josh Mandel) is on the ballot facing accused wife-beater Sherrod Brown; it may be more difficult to manage in some other races. And building a critical mass of such candidates (Mandel, Liljenquist, Mourdock, Ted Cruz in Texas, Jeff Flake in Arizona, Don Stenberg in Nebraska, Mark Neumann in Wisconsin, possibly a few others who haven’t proven themselves just yet) will make it easier to convince conservatives nationwide that even with Romney at the top, and even with some Senate races where we are resigned to moderates (Dean Heller, Scott Brown, Linda Lingle) or establishment-minded conservatives (George Allen), the party has not completely lost touch with the lessons of its victories in 2010.

In the presidential race, we go to war with the nominee we have. And we should unite behind him, because he’s the only thing standing between us and another term of Obama. But this is not Mitt Romney’s party, it’s ours. We deserve a Senate that will stand up to both Romney and Obama. That’s why it’s time for voters to give Lugar and Hatch the gold watch after 36 years in the Senate, and try something new.