WASHINGTON (AP) — Wyoming Sen. Mike Enzi is seeking the chairmanship up the Senate Budget Committee, setting up a showdown next month with Alabama Sen. Jeff Sessions for the important post.

Sessions is currently the top Republican on the Budget Committee but Enzi technically has seniority over Sessions even though both were elected to the Senate in 1996. A spokesman for Enzi confirmed Friday that Enzi is seeking the budget post.

Under Senate GOP rules, it's up to Republicans on the committee to elect their chairman, and the decision is almost always ratified by the party's full Senate membership. Seniority is a factor, but not the only one.

The panel's chief responsibility is to draft a budget blueprint each year that sets parameters for follow-up legislation. That so-called budget resolution and special follow-up legislation can't be filibustered and are likely to serve as the means by which congressional Republicans mount an attack on President Barack Obama's health care law next year.

Sessions has been the top Republican on the panel since 2011. He's taken a hard line on Obama's executive orders on immigration, siding with fellow conservatives like Sen. Ted Cruz, R-Texas, in support of using Congress' power of the purse to block Obama on immigration. Some Republicans fear such a move could lead to a government shutdown.

Both Enzi and Sessions were easily re-elected this month.