More Republicans in the United States describe their political views as conservative, a new Gallup poll shows.

Eighteen percent of Republicans -- including independents who lean Republican -- describe their political views as very conservative, while 53 percent are conservative and 29 percent are moderate or liberal, according to the poll released on Monday.

The percentage of Republicans who claim to be conservative or very conservative exceeds the 67 percent Gallup found in 2006 and the 62 percent in 2002 -- the last two midterm election years, indicating conservative bloc is growing in influence in the Republican Party.

The poll also shows that conservatives are more likely to be Protestant, much more likely to be religious, and are, on average, older than moderate or liberal Republicans. They also consist more heavily of men, whites, and those living in the South.

In that voter turnout is generally much greater among middle- aged and older Americans than among younger adults, it is likely that conservative Republicans have had an even greater voice in Republican Party primaries this year than their numbers suggest.

"Coupled with the expanded proportion of conservatives within the Republican ranks over the past decade, this may help explain the success of several Tea Party-backed Republican candidates this year against establishment Republicans. It also highlights the turnout advantage conservatives will likely have in the upcoming general elections," said Gallup.