Should Majority Whip Kevin McCarthy (R-CA) meet expectations and beat Rep. Raul Labrador (R-ID) in the race to replace House Majority Leader Eric Cantor, the Californian will leave another leadership vacancy to be filled.

The prospect of this opening already has members vying for the position. To date, Reps. Steve Scalise (R-LA), Marlin Stutzman (R-IN), and Peter Roskam (R-IL) have all tossed their hats into the ring for what could soon be McCarthy’s old job.

Scalise, the current chairman of the Republican Study Committee, and Stutzman, who came to office as a tea party candidate in 2010, appear to have more conservative leanings. Roskam is currently chief deputy whip. 

But what do the advocates say? 

Stutzman boasts the highest ratings from Heritage Action, which monitors lawmakers on key votes to determine how conservative they are. The Indiana lawmaker has an 84 percent rating for this Congress and an 87 percent lifetime rating from HA. Scalise is slightly lower, with an 81 percent rating for this Congress and an 81 percent lifetime rating, and Roskam brings up the rear with 52 percent and 56 percent ratings. 

The Club for Growth’s Congressional Scorecard, which looks at lawmakers’ records on what they deem to be “pro-growth” politics, showed a similar line, with Stutzman leading the pack (with a 2013 rating of 91 percent and a lifetime rating of 93 percent), followed by Scalise (rated 84 percent in 2013 and 90 percent lifetime), and finally Roskam (61 percent, 74 percent).

The American Conservative Union has Stutzman and Scalise neck and neck in their relative conservative ratings. In 2013, the ACU gave Stutzman a 96 percent rating and Scalise a 100 percent rating, Stutsman’s lifetime rating howecer is 99 percent, and Scalise’s is 98 percent. Roskam in 2013 received a 76 percent rating and has a lifetime record of 89 percent. 

On immigration matters, based on the pro-reduced immigration group Numbers USA, Stutzman and Scalise both have a 92 percent career record. This Congress, however, Scalise has a 62 percent rating and Stutzman has a 75 percent rating. Roskam this Congress has a 57 percent rating but a career 82 percent rating. 

In January, when Roll Call took a tally of where lawmakers stood on the House Republicans’ immigration principles — which stress enforcement first and include a path to citizenship for certain illegal immigrant children and legalization for non-criminal undocumented immigrants once they meet certain criteria — Stutzman told Roll Call he supported it. Scalise said he did not support it, and Roskam declined to comment. 

All three have 100 percent ratings from the National Right to Life Committee, and all have “As” from the National Rifle Association. Scalise, however, has an “A+.”