According to the Gallup statement, posted on CEO Frank Newport’s blog, the “evolving” worlds of journalism and opinion research provoked the two to reevaluate their relationship.

“For 20 years, Gallup has highly valued its partnership with USA Today,” Newport wrote. “During this time, the worlds of journalism and survey research have been changing and evolving ... given these shifts, Gallup and USA Today have made a mutual decision to move in independent directions beginning in 2013.”

USA Today released a similarly ambiguous statement.

“For 2013, USA TODAY and Gallup have made a mutual decision to move in different directions,” the paper said, according to a statement obtained by The Washington Post. “USA TODAY is in the final stages of negotiating an arrangement with another polling organization.”

The announcements follow a tumultuous year in the world of polling.

The 2012 election was marked by cries of bias from first one political party and then the other, provoking furious debate over the reliability of data proffered by various polling outlets.

Republicans said the surveys relied on voter sample sizes that gave too much weight to high Democratic turnout. Even Mitt Romney’s campaign got in the act, arguing pollsters relying on the 2008 turnout to determine the makeup of the 2012 electorate were mistaken.

Turnout in 2012 ended up similar to 2008, sending President Obama to an easy victory over Romney.

However, the Obama campaign at one point attacked a Gallup poll that showed Romney holding a 4-percentage-point lead in the swing states over the incumbent.

Democratic pollster Joel Benenson argued Gallup’s likely-voter screening method “created a bias against groups inclined to support Obama,” and was the reason the candidates were tied among women, traditionally an Obama stronghold.

Gallup was also criticized in mid-October when Obama’s job approval rating spiked, according to its daily tracking survey. The jump seemed to be the result of a shift in the polling outlet’s methodology, in which it increased the proportion of cellphones it surveyed.

“It’s common,” Newport told The Hill at the time, referring to criticism of polling techniques. “The campaigns have a war room-type mentality, and both campaigns feel the need to quickly jump on any news of any type that could be viewed as negative for their candidate.”