PRINCETON, NJ -- About four in 10 Republicans and Republican-leaning independents classify themselves as supporters of the Tea Party, while 11% are opponents and 48% are neither. This continues to be a significant drop from the Tea Party's high-water mark in November 2010, when 61% of Republicans were supporters of the Tea Party.

In the past three and a half years, levels of support and opposition for the Tea Party among Democrats and Democratic-leaning independents have changed relatively little.

These data are from a April 24-30 Gallup survey and underscore both the existing division of opinion in relationship to the Tea Party among Republicans and the shift in support since the last midterm election.

The role of the Tea Party in the selection of Republican nominees for Senate and House seats this year continues to be a high-profile issue. The Tea Party was perceived as suffering a setback on Tuesday, when Thom Tillis, the candidate widely perceived as representing the GOP establishment in the North Carolina Republican Senate primary, soundly defeated Greg Brannon, who was positioned as the Tea Party's choice. Tillis will now face incumbent North Carolina Democratic Sen. Kay Hagan in the fall general election.

The drop in support for the Tea Party among Republicans is mainly responsible for the drop in support among all Americans since November 2010, from 32% to today's 22%. Support has fluctuated in the intervening time period, but has been remarkably steady at 22% in the last three Gallup polls conducted since September of 2013. The percentage of Americans who classify themselves as Tea Party opponents, however, has risen to 30%, tied with two measurements in 2010 as the highest in the history of tracking this question.

Republican Tea Party Supporters Are Core, Conservative Republicans

The broad group of Republicans who are supporters of the Tea Party are remarkably similar to other Republicans across most demographic categories -- including race and ethnicity, income, age, education, or region of country. Republican Tea Party supporters are somewhat more likely to be weekly church attenders and slightly more likely to be men.

What then are the key factors that separate Republicans who support the Tea Party and those who do not? The answer to that question revolves mainly around ideology. Over half of Republicans who self-identify as conservatives are supporters of the Tea Party. Support for the Tea Party drops to 23% among moderate and liberal Republicans.

Ideology also plays a role in determining Democrats' attitudes toward the Tea Party. Conservative Democrats are relatively indifferent to the Tea Party, while moderate, and in particular liberal, Democrats are much more likely to classify themselves as opponents.

Tea Party Republicans Are Most Focused on the Midterm Elections

Republicans in general are usually more tuned in to midterm elections than those who are not Republicans -- but it is clear that within the broad group of those who identity with or lean toward the Republican party, Tea Party supporters are significantly more focused than other Republicans. Republican Tea Party supporters have given the election more thought, and also are significantly more likely to say they are more enthusiastic about voting, than either other Republicans or non-Republicans.

Bottom Line

The number of Tea Party supporters among Republicans has dropped by a third since November 2010, and opposition to the Tea Party in the general population has returned to its all-time high -- suggesting that the Tea Party will have less potential to affect elections this year than was the case in the last midterm election in 2010.

Tea Party support, more than anything else, appears to substantially correlate with the more straightforward characteristics of being a core, conservative Republican. Thus, these trends may suggest that the GOP is on a more moderate track in general. Clearly Mitt Romney's presidential nomination in 2012 was evidence of waning Tea Party support, and currently the Tea Party cannot even claim majority support of the GOP base, further hindering its influence to remake the party in its own image. The results of several high profile primary contests later this month will be important indicators of the reality of the Tea Party's influence. Still, whatever else happens, Tea Party supporters will continue to be a presence in American politics because of their apparent motivation and interest in election outcomes, factors that, more than likely, will translate into support for candidates, and higher Election Day turnout.