Washington (CNN) -- With a year to go before midterm congressional elections, a new national poll indicates that Americans are divided over whether they'd vote for the Democratic or Republican candidate in their district.
Fifty percent of people questioned in a CNN/Opinion Research Corp. survey released Tuesday say they would vote for the Democratic candidate if the election for the House of Representatives were held today, with 44 percent saying they'd back the Republican candidate. Five percent say they'd vote for neither major party candidate and 2 percent are undecided.
The 6-point advantage for the Democrats is at the edge of the poll's sampling error.
Other organizations' surveys conducted over the past two months also suggest a division among Americans when it comes to the generic ballot question, which asks a respondent if they would vote for a Democrat or Republican in their congressional district, without naming any specific candidates.
In November 2010, all 435 seats in the House and more than a third of the Senate seats are up for grabs. Democrats currently hold a 79-seat margin in the House of Representatives, with two seats vacant, and a 20 seat margin in the Senate.
According to the poll, Americans are also divided on whether they have made up their minds regarding the 2010 midterm contests, with 49 percent saying their minds are made up and 45 percent saying they could change their choice.
The survey also indicates that 46 percent of Republicans say they're enthusiastic about voting next year, with 39 percent of Democrats saying they're energized.
"When Democratic and Republican candidates for U.S. House square off a year from now, they may face a very different electorate than the one that put Barack Obama in power a year ago," said CNN Polling Director Keating Holland. "In 2008, Democratic voters were generally more enthusiastic about voting than Republicans; now it's the GOP's turn to benefit from an enthusiasm gap."
But President Obama, unlike Bill Clinton in 1994, appears to give Democratic candidates an advantage: The survey suggests that most registered voters say they are more likely to vote for a candidate for Congress who supports Obama. Four in 10 say they are more likely to vote for a candidate who opposes Obama.
"Historically, these tea leaves are very hard to read," Holland said.
Democrats and Republicans had virtually the same numbers a year before the 1994 midterm elections that put the GOP in power, he said, but the two parties also had roughly the same strength a year before the 2006 midterms that put the Democrats back in the saddle on Capitol Hill.
"Add to that the fact that nearly half of all voters say they could change their minds between now and election day 2010 and it's clear that any prediction would be futile," Holland said.
The CNN/Opinion Research Corp. poll was conducted October 30-November 1, with 952 registered voters questioned by telephone. The survey's overall sampling error is plus or minus 3 percentage points.