Primaries in Mississippi and New York will decide whether two major congressional figures will retain their standing in the upcoming elections in November.

United States Senator Thad Cochran, a Mississippi Republican, is facing a potential upset from Tea Party-backed state Senator Chris McDaniel.

Cochran, the third-most senior member of the Senate and second-most senior Republican, came in second in the June 3rd Mississippi primary, and a potential upset by the Tea Party challenger could mean a serious challenge to Republican power – especially after House Majority Leader Eric Cantor’s surprise upset from Tea Party challenger David Brat.

A recent article by Politico highlights that the biggest points of contention between Cochran and McDaniel are federal spending and both candidates’ “conservative credentials.”

Cochran is known for bringing home billions in federal aid for the state of Mississippi, the poorest state in the United States, but some believe the 76-year old senator should step down.

Strong conservative McDaniel focuses his campaign on national themes, however, and a transition to the Tea Party ideal of reduced federal spending. In a highly controversial interview, McDaniel even stated that he was not certain if he would have voted in favor of receiving federal aid after Hurricane Katrina in 2005.

Another top member of Congress facing a strong challenger is Harlem Democrat, Representative Charlie Rangel. Rangel’s challenger is state Senator Adriano Espaillat.

Rangel, an 84-year-old Democrat, has a political career spanning four decades, but his challenger, Dominican-born Espaillat is campaigning with support from the district’s changing demographics and increasing Hispanic population.

Primary elections will also be held in Colorado, Maryland, Oklahoma, and Utah on Tuesday, along with a run-off election in South Carolina.