Most Conservative Senators -- PICTURES

Key Conservative Stance: Tom Coburn, R-Okla., is a strong opponent of abortion rights; he sponsored bills requiring AIDS counseling for pregnant women and labels on condoms disclosing that they don’t prevent infections that lead to cervical cancer. He became known around the Capitol for conducting graphic slide shows for lawmakers and staff about the effects of sexually transmitted diseases. (SUE OGROCKI/AP)

Key Conservative Stance: Ron Johnson, R-Wis., said that his political views have been influenced by Ayn Rand’s 1957 novel Atlas Shrugged , which argues that civilization cannot exist where men are slaves to society and government. Johnson said that his motivation to run against Feingold was the senator’s support of the Democrats’ 2010 health care overhaul, which he called “the single greatest assault to our freedom in my lifetime.” (MANUEL BALCE CENETA/AP)

Key Conservative Stance: Mike Crapo, R-Idaho, during the 2009 health care debate sought to amend the bill in the committee to seek to prevent individuals making $200,000 annually and families earning $250,000 a year or less from being taxed to pay for the policy changes in the bill; it was defeated after Baucus called it a “killer amendment” that would deprive the legislation of needed revenue. (MATT CILLEY/AP)

Key Conservative Stance: Michael Enzi, R-Wyo., has been a reliable stalwart for the Right—his lifetime rating from the American Conservative Union through 2010 was above 93 percent, one of the highest among senators. He and Rep. Rob Bishop, R-Utah, pleased tea party activists in May 2011, when they introduced the “Repeal Amendment,” a measure enabling states to repeal any federal law. (HARAZ N. GHANBARI/AP)

Key Conservative Stance: John Barrasso, R-Wyo., has been a particularly vehement critic of the Environmental Protection Agency and introduced a bill in February 2011 to bar EPA from regulating greenhouse gases blamed for global warming. “This is not your parents’ EPA,” he said in a May 2011 speech. “Your parents’ EPA focused on rebuilding the environment. This EPA is focused on remaking society.” (J. SCOTT APPLEWHITE/AP)

Key Conservative Stance: David Vitter, R-La., cast one of the two votes against confirming New York Democrat Hillary Rodham Clinton as secretary of State, although her qualifications for the job were not an issue. Vitter has opposed much of the Obama administration's agenda. (ALEX BRANDON/AP)

Key Conservative Stance: Richard Burr, R-N.C., voted against the Senate immigration overhaul bill because he said it would lead to “blanket amnesty” for illegal immigrants. During negotiations on the compromise bill the following year, Burr supported the “touchback” amendment that would have forced illegal immigrants to return to their home countries before applying for visas. When the amendment was voted down, he voted against allowing the compromise bill to advance. (GERRY BROOME/AP)

Key Conservative Stance: James Risch, R-Idaho, opposed most of Obama’s spending initiatives, including a Senate-passed $35 billion jobs bill in February 2010 that he complained cost too much. “I ran for this office as a deficit hawk, and now that I am here I have moved even further in that direction,” he told The Idaho Statesman. (HARRY HAMBURG/AP)

Key Conservative Stance: James Inhofe, R-Okla., in February 2011 cosponsored a bill to stop EPA from regulating carbon-dioxide emissions and also limiting states’ authority to do so. After the April 2010 BP oil spill in the Gulf of Mexico, he opposed a Democratic initiative to remove the $75 million cap on damages for offshore-drilling accidents and argued that there should be some limit. (SUSAN WALSH/AP)

Key Conservative Stance: Jim DeMint, R-S.C., aggressively went on the attack against the new Democratic president. He tried to substitute President Obama’s 2009 economic-stimulus bill with one containing only tax cuts, and he tried to stop the advance of Obama’s health care initiative, famously telling Republicans in July 2009, “If we’re able to stop Obama on this, it will be his Waterloo. It will break him.” (J. SCOTT APPLEWHITE/AP)