Republicans Use Shutdown to Stake Positions for 2016 Bids During the federal government shutdown, Senator Marco Rubio of Florida has appeared guided by one goal: sticking as close as possible to Senator Ted Cruz of Texas. Eager to regain favor with conservatives as he considers running for president, Mr. Rubio has fully embraced Mr. Cruz's effort to block financing for the new health care law, standing with him at news conferences and through procedural maneuvers to that led to the shutdown. Even more tellingly, late in the evening on Sept. 24, Mr. Cruz dashed out of an elegant Capitol Hill fund-raiser for Gov. Terry E. Branstad of Iowa, attended by Republican establishment figures like the lobbyist Ron Kaufman, former Gov. Haley Barbour of Mississippi and the former White House counsel C. Boyden Gray, to join Mr. Cruz for his marathon speech against the health care law. "I want to thank the senator for his efforts here today, and in the weeks that have led us here," Mr. Rubio said as Mr. Cruz gladly yielded the floor. Mr. Rubio is not the only Republican using the shutdown to position himself for a presidential candidacy. These Republicans" actions, as the crisis drags on, offer an early glimpse of the contours of the 2016 primary: some in the emerging field are desperate to avoid being seen as to the left of Mr. Cruz and his fervent Tea Party supporters, while others are charting a different course. "Cruz is trying to start a wave of Salem witch trials in the G.O.P. on the shutdown and Obamacare, and that fear is impacting some people's calculations on 2016," said the Republican strategist Mike Murphy. The budget crisis, of course, is not only dominating the national news cycles. It is also being carefully watched by those in the Republican Party who will help determine the next nominee. For Mr. Rubio, who has fallen out of favor with the party's base after supporting efforts to overhaul immigration, the need to re-establish conservative credentials is especially urgent. Gov. Bobby Jindal of Louisiana seems equally worried about upsetting the party's base; he suffered blowback from Republican activists after delivering a stinging critique of his party in the wake of the 2012 presidential defeat, saying Republicans must avoid being seen as protecting the rich and should "stop being the stupid party." Now he is more measured. He declined in August to join a bipartisan group from the National Governors Association that warned Congress not to shut down the federal government, and last week he told reporters he would not "micromanage what's going on on the Hill or second-guess tactics." Gov. Chris Christie of New Jersey is seizing on the moment to distance himself from Republicans in Washington and its dysfunction. The governor, who is up for re-election next month, fires off near daily Twitter posts about his bipartisan achievements in his home state with the anti-Washington hashtag of #DearDC. His aides sent reporters a link to a video in which he announces, "I hope in Washington what they figure out is that what we pay them to do when we send them down there is to run the government, not to shut it down." Gov. Scott Walker of Wisconsin has been more restrained, avoiding a hashtag war, but has sounded similar notes, while former Gov. Jeb Bush of Florida appears to be assuming the role of the adult in the room, warning his party not to overreach, because of what he called the "dicey" politics. "It's embarrassing to see this play out as it has," Mr. Bush said. And I respect, there's deep - deeply held views on this. But you've got to pay your debts. "It all tells you what their political instincts are," Charles R. Black Jr., a Republican lobbyist who has worked on presidential campaigns for over 35 years, said of the maneuvering. Perhaps the most revealing repositioning is being undertaken by Senator Rand Paul of Kentucky. Mr. Paul is a libertarian-leaning first-term senator who was catapulted into office by passionate Tea Party enthusiasts, the constituency most supportive of the Republicans" hard-line stance on the shutdown. But as he looks at the 2016 contest, he is seeking to broaden his appeal beyond his Tea Party base, distancing himself from some inflammatory views held by his father, former Representative Ron Paul of Texas, as he grows closer with the Senate minority leader, Mitch McConnell of Kentucky, and courts more mainline Republican donors. Without turning off his die-hard ideological followers, Mr. Paul wants to send a message to the Republican establishment that he would run to win the nomination and not simply to carry the libertarian banner. Even while voting with Mr. Cruz and denouncing the health care law in television interviews, Mr. Paul has pitched ideas to defuse tension in Congress and bring about negotiations. Last week, he invited the entire House and Senate to join him for coffee on the steps of the Capitol. "Republicans and Democrats don't sit down and have a discussion enough," Mr. Paul wrote in the invitation to his colleagues. Maybe by chatting over coffee together we can just talk and see if we can get along. As far as attendance goes, the kaffeeklatsch was a bust: only seven lawmakers showed up, including one Democrat who seemed to teasingly spoof the whole idea by shouting "kumbaya!" But more than two dozen reporters showed up and duly recorded Mr. Paul's effort at cross-party comity, which was the point. What exasperates some pragmatic Republicans is that even would-be candidates like Mr. Paul who seek mainstream acceptance cannot bring themselves to completely detach from Mr. Cruz when the votes are called. Except for Representative Peter T. King, Republican of New York, who has floated himself as a potential presidential candidate, none of the likely contenders have yet been willing to directly take on Mr. Cruz, a recognition of the affection by the party's base for the senator. "Play your own music and stop being a cheap cover band," Mr. Murphy, the strategist, said, imploring 2016 aspirants to resist the temptation to "out-Cruz Cruz."